Old Irish

Old Irish
Goídelc
Pronunciation	[ˈɡoːi̯ðʲelɡ]
Region	Ireland, Isle of Man, western coast of Great Britain
Era	6th century–10th century; evolved into Middle Irish about the 10th century
Language family	Indo-European Celtic Insular Celtic Goidelic Old Irish
Early form	Primitive Irish
Writing system	Latin
Language codes
ISO 639-2	sga
ISO 639-3	sga
Glottolog	oldi1246
Linguasphere	50-AAA-ad

Old Irish (Goídelc; Irish: Sean-Ghaeilge; Scottish Gaelic: Seann Ghàidhlig; Manx: Shenn Yernish), sometimes called Old Gaelic, is the oldest form of the Goidelic languages for which extensive written texts are extant. It was used from c. 600 to c. 900. The primary contemporary texts are dated c. 700–850; by 900 the language had already transitioned into early Middle Irish. Some Old Irish texts date from the 10th century, although these are presumably copies of texts composed at an earlier time period. Old Irish is thus forebear to Modern Irish, Manx, and Scottish Gaelic.

Old Irish is known for having a particularly complex system of morphology and especially of allomorphy (more or less unpredictable variations in stems and suffixes in differing circumstances) as well as a complex sound system involving grammatically significant consonant mutations to the initial consonant of a word. Apparently, neither characteristic was present in the preceding Primitive Irish period, though initial mutations likely existed in a non-grammaticalized form in the prehistoric era. Much of the complex allomorphy was subsequently lost, but the sound system has been maintained with little change in the modern languages.

Contemporary Old Irish scholarship is still greatly influenced by the works of a small number of scholars active in the late 19th and early 20th centuries such as Rudolf Thurneysen (1857–1940) and Osborn Bergin (1873–1950).

Notable characteristics

Notable characteristics of Old Irish compared with other old Indo-European languages, are:

• Initial mutations, including lenition, nasalisation and aspiration/gemination.
• A complex system of verbal allomorphy.
• A system of conjugated prepositions that is unusual in Indo-European languages (though not entirely unparalleled, existing e.g. in modern Persian): dím "from me", dít "from you", dé "from him", dí "from her", dín "from us", díb "from you", diib "from them" (basic preposition di "from"). There is a great deal of allomorphy here, as well.
• Infixed object prepositions, which are inserted between the verb stem and its prefix(es). If a verb lacks any prefixes, a dummy prefix is normally added.
• Special verbal conjugations are used to signal the beginning of a relative clause.

Old Irish also preserves most aspects of the complicated Proto-Indo-European (PIE) system of morphology. Nouns and adjectives are declined in three genders (masculine, feminine, neuter); three numbers (singular, dual, plural); and five cases (nominative, vocative, accusative, dative and genitive). Most PIE noun stem classes are maintained (o-, yo-, ā-, yā-, i-, u-, r-, n-, s-, and consonant stems). Most of the complexities of PIE verbal conjugation are also maintained, and there are new complexities introduced by various sound changes (see below).

Classification

Old Irish was the only member of the Goidelic/Gaelic branch of the Celtic languages, which is, in turn, a subfamily of the wider Indo-European language family that also includes the Slavonic, Italic/Romance, Indo-Aryan and Germanic subfamilies, along with several others. Old Irish is the ancestor of all modern Goidelic languages: Modern Irish, Scottish Gaelic and Manx.

A still older form of Irish is known as Primitive Irish. Fragments of Primitive Irish, mainly personal names, are known from inscriptions on stone written in the Ogham alphabet. The inscriptions date from about the 4th to the 6th centuries. Primitive Irish appears to have been very close to Common Celtic, the ancestor of all Celtic languages, and it had a lot of the characteristics of other archaic Indo-European languages.

Sources

Relatively little survives in the way of strictly contemporary sources. They are represented mainly by shorter or longer glosses on the margins or between the lines of religious Latin manuscripts, most of them preserved in monasteries in Germany, Italy, Switzerland, France and Austria, having been taken there by early Irish missionaries. Whereas in Ireland, many of the older manuscripts appear to have been worn out through extended and heavy use, their counterparts on the Continent were much less prone to the same risk because once they ceased to be understood, they were rarely consulted.

The earliest Old Irish passages may be the transcripts found in the Cambrai Homily, which is thought to belong to the early 8th century. The Book of Armagh contains texts from the early 9th century. Important Continental collections of glosses from the 8th and 9th century include the Würzburg Glosses (mainly) on the Pauline Epistles, the Milan Glosses on a commentary to the Psalms and the St Gall Glosses on Priscian's Grammar.

Further examples are found at Karlsruhe (Germany), Paris (France), Milan, Florence and Turin (Italy). A late 9th-century manuscript from the abbey of Reichenau, now in St. Paul in Carinthia (Austria), contains a spell and four Old Irish poems. The Liber Hymnorum and the Stowe Missal date from about 900 to 1050.

In addition to contemporary witnesses, the vast majority of Old Irish texts are attested in manuscripts of a variety of later dates. Manuscripts of the later Middle Irish period, such as the Lebor na hUidre and the Book of Leinster, contain texts, which are thought to derive from written exemplars in Old Irish now lost and retain enough of their original form to merit classification as Old Irish.

The preservation of certain linguistic forms current in the Old Irish period may provide reason to assume that an Old Irish original directly or indirectly underlies the transmitted text or texts.

Phonology

Consonants

The consonant inventory of Old Irish is shown in the chart below. The complexity of Old Irish phonology is from a four-way split of phonemes inherited from Primitive Irish, with both a fortis–lenis and a "broad–slender" (velarised vs. palatalised) distinction arising from historical changes. The sounds /f v θ ð x ɣ h ṽ n l r/ are the broad lenis equivalents of broad fortis /p b t d k ɡ s m N L R/; likewise for the slender (palatalised) equivalents. (However, most /f fʲ/ sounds actually derive historically from /w/.)

		Labial	Dental	Alveolar	Velar	Glottal
Nasal	broad	m	N  n		ŋ
	slender	mʲ	Nʲ  nʲ		ŋʲ
Plosive	broad	p  b	t  d		k  ɡ
	slender	pʲ  bʲ	tʲ  dʲ		kʲ  ɡʲ
Fricative	broad	f  v	θ  ð	s	x  ɣ	h
	slender	fʲ  vʲ	θʲ  ðʲ	sʲ	xʲ  ɣʲ	hʲ
Nasalized fricative	broad	ṽ
	slender	ṽʲ
Approximant	broad		R  r
	slender		Rʲ  rʲ
Lateral	broad		L  l
	slender		Lʲ  lʲ

Some details of Old Irish phonetics are not known. /sʲ/ may have been pronounced [ɕ] or [ʃ], as in Modern Irish. /hʲ/ may have been the same sound as /h/ or /xʲ/. The precise articulation of the fortis sonorants /N/, /Nʲ/, /L/, /Lʲ/, /R/, /Rʲ/ is unknown, but they were probably longer, tenser and generally more strongly articulated than their lenis counterparts /n/, /nʲ/, /l/, /lʲ/, /r/, /rʲ/, as in the Modern Irish and Scottish dialects that still possess a four-way distinction in the coronal nasals and laterals. /Nʲ/ and /Lʲ/ may have been pronounced [ɲ] and [ʎ] respectively. The difference between /R(ʲ)/ and /r(ʲ)/ may have been that the former were trills while the latter were flaps. /m(ʲ)/ and /ṽ(ʲ)/ were derived from an original fortis–lenis pair.

Vowels

Old Irish had distinctive vowel length in both monophthongs and diphthongs. Short diphthongs were monomoraic, taking up the same amount of time as short vowels, while long diphthongs were bimoraic, the same as long vowels. (This is much like the situation in Old English but different from Ancient Greek whose shorter and longer diphthongs were bimoraic and trimoraic, respectively: /ai/ vs. /aːi/.) The inventory of Old Irish long vowels changed significantly over the Old Irish period, but the short vowels changed much less.

The following short vowels existed:

	Monophthongs		Diphthongs
Close	i	u	ĭu
Mid	e	o	ĕu	(ŏu)1
Open	a		ău

¹The short diphthong ŏu may have existed very early in the Old Irish period/but not later on.

Archaic Old Irish (before about 750) had the following inventory of long vowels:

	Monophthongs		Diphthongs
Close	iː	uː	iu	ui
Mid	e₁ː, e₂ː1	o₁ː, (o₂ː?)2	eu	oi, (ou)3
Open	aː		ai, au3

¹Both /e₁ː/ and /e₂ː/ were normally written é but must have been pronounced differently because they have different origins and distinct outcomes in later Old Irish. /e₁ː/ stems from Proto-Celtic *ē (< PIE *ei), or from ē in words borrowed from Latin. e₂ː generally stems from compensatory lengthening of short *e because of loss of the following consonant (in certain clusters) or a directly following vowel in hiatus. It is generally thought that /e₁ː/ was higher than /e₂ː/. Perhaps /e₁ː/ was [eː] while /e₂ː/ was [ɛː]. They are clearly distinguished in later Old Irish, in which /e₁ː/ becomes ía (but é before a palatal consonant). /e₂ː/ becomes é in all circumstances. Furthermore, /e₂ː/ is subject to u-affection, becoming éu or íu, while /e₁ː/ is not.

²A similar distinction may have existed between /o₁ː/ and /o₂ː/, both written ó, and stemming respectively from former diphthongs (*eu, *au, *ou) and from compensatory lengthening. However, in later Old Irish both sounds appear usually as úa, sometimes as ó, and it is unclear whether /o₂ː/ existed as a separate sound any time in the Old Irish period.

³/ou/ existed only in early archaic Old Irish (c.700 or earlier); afterwards it merged into /au/. Neither sound occurred before another consonant, and both sounds became ó in later Old Irish (often ú or u before another vowel). The late ó does not develop into úa, suggesting that áu > ó postdated ó > úa.

Later Old Irish had the following inventory of long vowels:

	Monophthongs		Diphthongs
Close	iː	uː	iu, ia	ui, ua
Mid	eː	oː	eu	oi?1
Open	aː

¹Early Old Irish /ai/ and /oi/ merged in later Old Irish. It is unclear what the resulting sound was, as scribes continued to use both aí and oí to indicate the merged sound. The choice of /oi/ in the table above is somewhat arbitrary.

The distribution of short vowels in unstressed syllables is a little complicated. All short vowels may appear in absolutely final position (at the very end of a word) after both broad and slender consonants. The front vowels /e/ and /i/ are often spelled ae and ai after broad consonants, which might indicate a retracted pronunciation here, perhaps something like [ɘ] and [ɨ]. All ten possibilities are shown in the following examples:

Old Irish	Pronunciation	English	Annotations
marba	/ˈmarva/	kill	1 sg. subj.
léicea	/ˈLʲeːɡʲa/	leave	1 sg. subj.
marbae	/ˈmarve/ ([ˈmarvɘ]?)	kill	2 sg. subj.
léice	/ˈLʲeːɡʲe/	leave	2 sg. subj.
marbai	/ˈmarvi/ ([ˈmarvɨ]?)	kill	2 sg. indic.
léici	/ˈlʲeːɡʲi/	leave	2 sg. indic.
súlo	/ˈsuːlo/	eye	gen.
doirseo	/ˈdoRʲsʲo/	door	gen.
marbu	/ˈmarvu/	kill	1 sg. indic.
léiciu	/ˈLʲeːɡʲu/	leave	1 sg. indic.

The distribution of short vowels in unstressed syllables, other than when absolutely final, was quite restricted. It is usually thought that there were only two allowed phonemes: /ə/ (written a, ai, e or i depending on the quality of surrounding consonants) and /u/ (written u or o). The phoneme /u/ tended to occur when the following syllable contained an *ū in Proto-Celtic (for example, dligud /ˈdʲlʲiɣuð/ "law" (dat.) < PC *dligedū), or after a broad labial (for example, lebor /ˈLʲevur/ "book"; domun /ˈdoṽun/ "world"). The phoneme /ə/ occurred in other circumstances. The occurrence of the two phonemes was generally unrelated to the nature of the corresponding Proto-Celtic vowel, which could be any monophthong: long or short.

Long vowels also occur in unstressed syllables. However, they rarely reflect Proto-Celtic long vowels, which were shortened prior to the deletion (syncope) of inner syllables. Rather, they originate in one of the following ways:

• from the late resolution of a hiatus of two adjacent vowels (usually as a result of loss of *s between vowels);
• from compensatory lengthening in response to loss of a consonant (cenél "kindred, gender" < *cenethl; du·air-chér "I have purchased" < *-chechr, preterite of crenaid "buys");
• from assimilation of an unstressed vowel to a corresponding long stressed vowel;
• from late compounding;
• from lengthening of short vowels before unlenited /m, N, L, R/, still in progress in Old Irish (compare erríndem "highest" vs. rind "peak").

Stress

Stress is generally on the first syllable of a word. However, in verbs it occurs on the second syllable when the first syllable is a clitic (the verbal prefix as- in as·beir /asˈberʲ/ "he says"). In such cases, the unstressed prefix is indicated in grammatical works with a following centre dot (·).

Orthography

As with most medieval languages, the orthography of Old Irish is not fixed, so the following statements are to be taken as generalisations only. Individual manuscripts may vary greatly from these guidelines.

The Old Irish alphabet consists of the following eighteen letters of the Latin alphabet:

a, b, c, d, e, f, g, h, i, l, m, n, o, p, r, s, t, u,

in addition to the five long vowels, shown by an acute accent (´):

á, é, í, ó, ú,

the lenited consonants denoted with a superdot (◌̇):

ḟ, ṡ,

and the eclipsis consonants also denoted with a superdot:

ṁ, ṅ.

Old Irish digraphs include the lenition consonants:

ch, fh, th, ph, sh,

the eclipsis consonants:

md, nd, ng; ṁd, ṅd, ṅg,

the geminatives:

bb, cc, ll, mm, nn, pp, rr, tt,

and the diphthongs:

aé/áe/aí/ái, oé/óe/oí/ói,

uí, ía, áu, úa, éu, óu, iu, au, eu,

ai, ei, oi, ui; ái, éi, ói, úi.

The following table indicates the broad pronunciation of various consonant letters in various environments:

Broad consonant phonemes
Letter	Word-initial			Non-initial
	unmutated	eclipsed	lenited	single	geminate
b	/b/	⟨mb⟩ /m/	/v/		⟨bb⟩ /b/
c	/k/	/ɡ/	⟨ch⟩ /x/	/k/,/g/	⟨cc⟩ /k/
d	/d/	⟨nd⟩ /N/	/ð/		—
f	/f/	/v/	⟨ḟ/fh⟩ / /	/f/	—
g	/ɡ/	⟨ng⟩ /ŋ/	/ɣ/		—
h	See explanation below
l	/L/	—	/l/		⟨ll⟩ /L/
m	/m/	—	/ṽ/		⟨mm⟩ /m/
n	/N/	—	/n/		⟨nn⟩ /N/
p	/p/	/b/	⟨ph⟩ /f/	/p/, /b/	⟨pp⟩ /p/
r	/R/	—	/r/		⟨rr⟩ /R/
s	/s/	—	⟨ṡ/sh⟩ /h/	/s/	—
t	/t/	/d/	⟨th⟩ /θ/	/t/, /d/	⟨tt⟩ /t/

Angle brackets ⟨⟩ here indicate graphemic differences to the unmutated consonant.

A dash (—) here indicates that the respective consonant is not subject to eclipsis. These consonants are: r, l, n, s

When the consonants b, d, g are eclipsed by the preceding word (always from a word-initial position), their spelling and pronunciation change to: ⟨mb⟩ /m/, ⟨nd⟩ /N/, ⟨ng⟩ /ŋ/

Generally, geminating a consonant ensures its unmutated sound. While the letter ⟨c⟩ may be voiced /g/ at the end of some words, but when it's written double ⟨cc⟩ it's always voiceless /k/ in regularised texts; however, even final /k/ was often written "cc", as in bec / becc "small, little" (Modern Irish and Scottish beag, Manx beg).

In later Irish manuscripts, lenited f and s are denoted with the letter h ⟨fh⟩, ⟨sh⟩, instead of using a superdot ⟨ḟ⟩, ⟨ṡ⟩.

When initial s stemmed from Primitive Irish *sw-, its lenited version is ⟨f⟩ [ɸ].

The slender (palatalised) variants of the 13 consonants are denoted with /ʲ/ marking the letter. They occur in the following environments:

• Before a written e, é, i, í
• After a written i, when not followed by a vowel letter (but not after the diphthongs aí, oí, uí)

Although Old Irish has both a sound /h/ and a letter h, there is no consistent relationship between the two. Vowel-initial words are sometimes written with an unpronounced h, especially if they are very short (the Old Irish preposition i "in" was sometimes written hi) or if they need to be emphasised (the name of Ireland, Ériu, was sometimes written Hériu). On the other hand, words that begin with the sound /h/ are usually written without it: a ór /a hoːr/ "her gold". If the sound and the spelling co-occur, it is by coincidence, as ní hed /Nʲiː heð/ "it is not".

Stops following vowels

The voiceless stops of Old Irish are c, p, t. They contrast with the voiced stops g, b, d. Additionally, the letter m can behave similarly to a stop following vowels. These seven consonants often mutate when not in the word-initial position.

In non-initial positions, the single-letter voiceless stops c, p, and t become the voiced stops /g/, /b/, and /d/ respectively unless they are written double. Ambiguity in these letters' pronunciations arises when a single consonant follows an l, n, or r. The lenited stops ch, ph, and th become /x/, /f/, and /θ/ respectively.

Non-initial voiceless stops ⟨c⟩, ⟨p⟩, ⟨t⟩
Old Irish	Pronunciation	English
macc	/mak/	son
bec or becc	/bʲeɡ/	small
op or opp	/ob/	refuse
bratt	/brat/	mantle
brot or brott	/brod/	goad
Lenited consonants ⟨ch⟩, ⟨ph⟩, ⟨th⟩
ech	/ex/	horse
oíph	/oif/	beauty
áth	/aːθ/	ford

The voiced stops g, b, and d become fricative /v/, /ð/, and /ɣ/, respectively—identical sounds to their word-initial lenitions.

Non-initial voiced stops ⟨g⟩, ⟨b⟩, ⟨d⟩
Old Irish	Pronunciation	English
dub	/duv/	black
mod	/moð/	work
mug	/muɣ/	slave
claideb	/klaðʲəv/	sword
claidib	/klaðʲəvʲ/	swords

In non-initial positions, the letter m usually becomes the nasal fricative /ṽ/, but in some cases it becomes a nasal stop, denoted as /m/. In cases in which it becomes a stop, m is often written double to avoid ambiguity.

Non-initial consonant ⟨m⟩
Old Irish	Pronunciation	English
dám	/daːṽ/	company
lom or lomm	/Lom/	bare

Stops following other consonants

Ambiguity arises in the pronunciation of the stop consonants (c, g, t, d, p, b) when they follow l, n, or r:

Homographs involving ⟨l⟩, ⟨n⟩, ⟨r⟩
Old Irish	Pronunciation	English
derc	/dʲerk/	hole
derc	/dʲerɡ/	red
daltae	/daLte/	fosterling
celtae	/kʲeLde/	who hide
anta	/aNta/	of remaining
antae	/aNde/	who remain

After m, the letter b is naturally a stop /b/. After d, l, r, the letter b is fricative /v/:

Consonant ⟨b⟩
Old Irish	Pronunciation	English
imb	/imʲbʲ/	butter
odb	/oðv/	knot (in a tree)
delb	/dʲelv/	image
marb	/marv/	dead

After n or r, the letter d is a stop /d/:

Consonant ⟨d⟩
Old Irish	Pronunciation	English
bind	/bʲiNʲdʲ/	melodious
cerd	/kʲeRd/	art, skill

After n, l, or r, the letter g is usually a stop /g/, but it becomes a fricative /ɣ/ in a few words:

Consonant ⟨g⟩
Old Irish	Pronunciation	English
long	/Loŋɡ/	ship
delg or delc	/dʲelɡ/	thorn
argat or arggat	/arɡəd/	silver
ingen	/inʲɣʲən/	daughter
ingen	/iNʲɡʲən/	nail, claw
bairgen	/barʲɣʲən/	loaf of bread

The consonants l, n, r

The letters l, n, r are generally written double when they indicate tense sonorants and single when they indicate lax sonorants. Originally, it reflected an actual difference between single and geminate consonants, as tense sonorants in many positions (such as between vowels or word-finally) developed from geminates. As the gemination was lost, the use of written double consonants was repurposed to indicate tense sonorants. Doubly written consonants of this sort do not occur in positions where tense sonorants developed from non-geminated Proto-Celtic sonorants (such as word-initially or before a consonant).

Old Irish	Pronunciation	English
corr	/koR/	crane
cor	/kor/	putting
coll	/koL/	hazel
col	/kol/	sin
sonn	/soN/	stake
son	/son/	sound
ingen	/inʲɣʲən/	daughter
ingen	/iNʲɡʲən/	nail, claw

Geminate consonants appear to have existed since the beginning of the Old Irish period, but they were simplified by the end, as is generally reflected by the spelling. Although, ll, mm, nn, rr were eventually repurposed to indicate nonlenited variants of those sounds in certain positions.

Vowels

Written vowels a, ai, e, i in poststressed syllables (except when absolutely word-final) all seem to represent phonemic /ə/. The particular vowel that appears is determined by the quality (broad vs. slender) of the surrounding consonants and has no relation to the etymological vowel quality:

Preceding consonant	Following consonant	Spelling	Example
broad	broad	⟨a⟩	dígal /ˈdʲiːɣəl/ "vengeance" (nom.)
broad	slender (in open syllable)	⟨a⟩
broad	slender (in closed syllable)	⟨ai⟩	dígail /ˈdʲiːɣəlʲ/ "vengeance" (acc./dat.)
slender	broad	⟨e⟩	dliged /ˈdʲlʲiɣʲəð/ "law" (acc.)
slender	slender	⟨i⟩	dligid /ˈdʲlʲiɣʲəðʲ/ "law" (gen.)

It seems likely that spelling variations reflected allophonic variations in the pronunciation of /ə/.

History

Old Irish was affected by a series of phonological changes that radically altered its appearance compared with Proto-Celtic and older Celtic languages (such as Gaulish, which still had the appearance of typical early Indo-European languages such as Latin or Ancient Greek). The changes were such that Irish was not recognized as Indo-European at all for much of the 19th century. The changes must have happened quite rapidly, perhaps in only one or two hundred years around 500–600, because almost none of the changes are visible in Primitive Irish (4th to 6th centuries), and all of them are already complete in archaic Old Irish (8th century). A capsule summary of the most important changes is (in approximate order):

1. Syllable-final *n (from PIE *m, *n) assimilated to the following phoneme, even across word boundaries in the case of syntactically connected words.
   • Voiceless stops became voiced: *mp *nt *nk > /b d ɡ/.
   • Voiced stops became prenasalised /ᵐb, ⁿd, ᵑɡ/. They were reduced to simple nasals during the Old Irish period.
   • Before a vowel, /n-/ was attached to the beginning of the syllable.
2. Lenition of all single consonants between vowels. That applied across word boundaries in the case of syntactically connected words.
   • Stops became fricatives.
   • *s became /h/ (later lost unless the following syllable was stressed).
   • *w was eventually lost (much later).
   • *m became a nasalised continuant (/w̃/; perhaps [w̃] or [β̃]).
   • *l *n *r remained, but the non-lenited variants were strengthened to /L N R/ (see phonology section above).
3. Extensive umlaut ("affection") of short vowels, which were raised or lowered to agree with the height of following Proto-Celtic vowels. Similarly, rounding of *a to /o/ or /u/ often occurred adjacent to labial consonants.
4. Palatalization of all consonants before front vowels.
5. Loss of part or all of final syllables.
6. Loss of most interior vowels (syncope).

They led to the following effects:

• Both the palatalised ("slender") and lenited variants of consonants were phonemicised, multiplying the consonant inventory by four (broad, broad lenited, slender, slender lenited). Variations between broad and slender became an important part of the grammar:
  • in masc. o-stems: macc "son" (nom. acc.) vs. maicc (gen.), cúl "back" (nom. acc.) vs. cúil (gen.), cf. Latin -us (nom.), -um (acc.) vs. -ī (gen.);
  • in fem. ā-stems: túath "tribe, people" (nom.) vs. túaith (acc. dat.), mucc "pig" (nom.) vs. muicc (acc. dat.);
  • in r-stems: athar "father" (gen.) vs. ath(a)ir (nom. acc. dat.).
• Lenition and nasal assimilation across word boundaries in syntactically connected words produced extensive sandhi effects (Irish initial mutations). The variations became an important part of the grammar.
• Both umlaut (vowel affection) and especially syncope radically increased the amount of allomorphy found across declensions and conjugations. The most dramatic deviations are due to syncope: compare as·berat "they say" vs. ní-epret "they do not say" or do·rósc(a)i "he surpasses" vs. ní-derscaigi "he does not surpass" (where the stressed syllable is boldfaced).

Examples of changes

The following are some examples of changes between Primitive Irish and Old Irish.

Primitive Irish	Old Irish	Meaning
inigena	ingen	daughter
qrimitir	cruimther	priest
maqqi	maicc	son (gen.)
velitas	filed	poet (gen.)
Lugudeccas	Luigdech	genitive of Lug(u)id (name)
Anavlamattias	Anfolmithe	genitive of Anblamath (name)
Coillabotas	Coílbad	genitive of name

Allomorphy

These various changes, especially syncope, produced quite complex allomorphy, because the addition of prefixes or various pre-verbal particles (proclitics) in Proto-Celtic changed the syllable containing the stress: According to the Celtic variant of Wackernagel's law, the stress fell on the second syllable of the verbal complex, including any prefixes and clitics. By the Old Irish period, most of this allomorphy still remained, although it was rapidly eliminated beginning in the Middle Irish period.

Among the most striking changes are in prefixed verbs with or without pre-verbal particles. With a single prefix and without a proclitic, stress falls on the verbal root, which assumes the deuterotonic ("second-stressed") form. With a prefix and also with a proclitic, stress falls on the prefix, and the verb assumes the prototonic ("first-stressed") form. Rather extreme allomorphic differences can result:

Example differences between deuterotonic and prototonic forms of various verbs. Stress falls directly after the center dot or hyphen.

Earlier form	Deuterotonic	Meaning	Prototonic	Meaning
*ess-bero(n)t < PIE *-bʰeronti	as·berat /as-ˈbʲerəd/	they say	ní-epret /Nʲiː-ˈhebrʲəd/	they do not say
*cum-uss-ana	con·osna	he rests	ní-cumsana	he does not rest
*de-ro-uss-scochi	do·rósc(a)i	he surpasses	ní-derscaigi	he does not surpass
*de-lugi < PIE *-logʰeyeti	do·lug(a)i	he pardons	ní-dílg(a)i	he does not pardon
*de-ro-gn...	do·róna	he may do	ní-derna	he may not do

The following table shows how these forms might have been derived:

Possible derivation of some verbal forms

	"they say"	"they do not say"	"he rests"	"he does not rest"	"he surpasses"	"he does not surpass"
Post-PIE	eks bʰeronti	nē eks bʰeronti	kom uks h₂eneh₂ti	nē kom uks h₂eneh₂ti	dē pro uks skokeyeti	nē dē pro uks skokeyeti
Proto-Celtic	eks ˈberonti	nī ˈeks-beronti	kom ˈuks-anāti	nī ˈkom-uks-anāti	dī ˈɸro-uks-skokīti	nī ˈdī-ɸro-uks-skokīti
Early Irish	ess-es ˈberont	ní-s ˈess-beront	kon-es ˈuss-anát	ní-s ˈkom-uss-anát	dí-s ˈro-uss-skokít	ní-s ˈdi-ro-uss-skokít
Nasal assimilation	ess-es ˈberodd	ní-s ˈess-berodd	—	—	—	—
Lenition	es-eh ˈberod	Ní-h ˈes-berod	kon-eh ˈus-anáθ	Ní-h ˈkow̃-us-anáθ	dí-h ˈRo-us-skoxíθ	Ní-h ˈdi-ro-us-skoxíθ
Palatalization	es-eh ˈbʲerod	Nʲí-h ˈes-bʲerod	—	Nʲí-h ˈkow̃-us-anáθ	dʲí-h ˈRo-us-skoxʲíθ	Nʲí-h ˈdʲi-ro-us-skoxʲíθ
Hiatus reduction	—	—	—	—	dʲí-h ˈRós-skoxʲíθ	Nʲí-h ˈdʲi-rós-skoxʲíθ
Umlaut (vowel affection)	—	—	kon-eh ˈos-anáθ	Nʲí-h ˈkuw̃-us-anáθ	—	Nʲí-h ˈdʲe-rós-skoxʲíθ
Shortening of absolutely final vowel	—	—	—	—	—	—
Loss/assimilation of final consonant(s)	es-e bʲ-ˈbʲerod	Nʲí h-ˈes-bʲerod	kon-e h-ˈos-aná	Nʲí k-ˈkuw̃-us-aná	dʲí R-ˈRós-skoxʲí	Nʲí d-ˈdʲe-rós-skoxʲí
Mora reduction in unstressed final vowel	es bʲ-ˈbʲerod	—	kon h-ˈos-ana	Nʲí k-ˈkuw̃-us-ana	dʲí R-ˈRós-skoxʲi	Nʲí d-ˈdʲe-rós-skoxʲi
Consonant assimilation	es ˈbʲerod	Nʲí h-ˈebʲ-bʲerod	—	—	—	—
Syncope	es ˈbʲerod	Nʲí h-ˈebʲbʲrod	kon h-ˈosna	Nʲí k-ˈkuw̃sana	dʲí R-ˈRósskxʲi	Nʲíd-ˈdʲersskoxʲi
Further consonant assimilation	—	Nʲí h-ˈebʲbʲrʲod	kon ˈosna	—	dʲí R-ˈRósski	Nʲíd-ˈdʲerskoxʲi
Unstressed vowel reduction	es ˈbʲerəd	Nʲí h-ˈebʲbʲrʲəd	—	Nʲí k-ˈkuw̃səna	di R-ˈRósski	Nʲí d-ˈdʲerskəxʲi
Prepositional modification	as ˈbʲerəd	—	—	—	do R-ˈRósski	—
Geminate reduction (non-vocalic-adjacent); sandhi geminate reduction	as·ˈbʲerəd	Nʲíh-ˈebrʲəd	kon·ˈosna	Nʲí-ˈkuw̃səna	do·ˈRóski	Nʲí-ˈdʲerskəxʲi
Fricative voicing between unstressed syllables	—	—	—	—	—	Nʲíd-ˈdʲerskəɣʲi
Old Irish pronunciation	as·ˈbʲerəd	Nʲí-h-ˈebrʲəd	kon·ˈosna	Nʲí-ˈkuw̃səna	do·ˈRóski	Nʲí-ˈdʲerskəɣʲi
Old Irish spelling	as·berat	ní-epret	con·osna	ní-(c)cumsana	do·rósc(a)i	ní-(d)derscaigi

The most extreme allomorphy of all came from the third person singular of the s-subjunctive because an athematic person marker -t was used, added directly onto the verbal stem (formed by adding -s directly onto the root). That led to a complex word-final cluster, which was deleted entirely. In the prototonic form (after two proclitics), the root was unstressed and thus the root vowel was also deleted, leaving only the first consonant:

Examples of extreme allomorphy of 3rd person singular s-subjunctive, conjunct

	Present Indicative				Present Subjunctive
	Positive (Deuterotonic)		Negative (Prototonic)		Positive (Deuterotonic)		Negative (Prototonic)
	Primitive Irish	Old Irish	Primitive Irish	Old Irish	Primitive Irish	Old Irish	Primitive Irish	Old Irish
"he refuses"	*uss ˈbond-et(i)	as·boind	*nís ˈuss-bond-et(i)	ní op(a)ind /obənʲdʲ/	*uss 'bod-s-t	as·bó	*nís ˈuss-bod-s-t	ní op /ob/
"he remains over"	*di ˈwo-uss-ret-et(i)	do·fúarat	*nís ˈdi-wo-uss-ret-et(i)	ní díurat	*di ˈwo-uss-ret-s-t	do·fúair	*nís ˈdi-wo-uss-ret-s-t	ní diúair
"he repeats, amends"	*ad ˈess-reg-et(i)	ad·eirrig	*nís ˈ*ad-ess-reg-et(i)	(ní aithrig?? >) ní aithirrig	*ad ˈess-reg-s-t	ath·e(i)rr	*nís ˈad-ess-reg-s-t	ní aithir
"he can"	*con ˈink-et(i)	com·ic	*nís ˈcom-ink-et(i)	ní cum(a)ic > ní cum(u)ing, ní cumaing	*con ˈink-s-t	con·í	*nís ˈcom-ink-s-t, *nís ˈcom-ink-ā-t	ní cum, ní cumai
"it happens"	*ad ˈcom-ink-et(i)	(ad·cum(a)ic >) ad·cumaing	*nís ˈad-com-ink-et(i)	(ní ecm(a)ic >) ní ecmaing	*ad ˈcom-ink-ā-t	ad·cumai	*nís ˈad-com-ink-ā-t	ní ecm(a)i

Syncope in detail

In more detail, syncope of final and intervocalic syllables involved the following steps (in approximate order):

• Shortening of absolutely final long vowels.
• Loss of most final consonants, including *m, *n, *d, *t, *k, and all clusters involving *s (except *rs, *ls, where only the *s is lost).
• Loss of absolutely final short vowels (including those that became final as a result of loss of a final consonant and original long final vowels).
• Shortening of long vowels in unstressed syllables.
• Collapsing of vowels in hiatus (producing new unstressed long vowels).
• Syncope (deletion) of vowels in every other interior unstressed syllable following the stress. If there are two remaining syllables after the stress, the first one loses its vowel; if there are four remaining syllables after the stress, the first and third lose their vowel.
• Resolution of impossible clusters resulting from syncope and final-vowel deletion:
  • Adjacent homorganic obstruents where either sound was a fricative became a geminate stop, voiceless if either sound was voiceless (e.g. *ðð *dð *ðd > /dd/; *θð *ðθ *θd *tθ etc. > /tt/).
  • Otherwise, adjacent obstruents assumed the voicing of the second consonant (e.g. *dt > /tt/; *kd > /gd/; *ɣt > /xt/).
  • *l *r *n not adjacent to a vowel became syllabic and then had a vowel inserted before them (e.g. domun "world" < *domn < *domnos < *dumnos; immormus "sin" < *imm-ro-mess). However, in the case of *n, that occurred only when the nasal had not previously been joined to a following voiced stop as a result of nasal assimilation: compare frecnd(a)irc "present" (disyllabic).
  • Remaining impossible clusters were generally simplified by deletion of consonants not adjacent to vowels (such as between other consonants). However, Old Irish tolerated geminates adjacent to other consonants as well other quite complex clusters: ainm /aNʲm/ "name" (one syllable), fedb /fʲeðβ/ "widow", do-aidbdetar /do-ˈaðʲβʲðʲədər/ "they are shown".

Proto-Celtic short vowels, vowel affection

All five Proto-Celtic short vowels (*a, *e, *i, *o, *u) survived into Primitive Irish more or less unchanged in stressed syllables.

However, during the runup to Old Irish, several mutations (umlauts) take place. Former vowels are modified in various ways depending on the following vowels (or sometimes surrounding consonants). The mutations are known in Celtic literature as affections or infections such as these, the most important ones:

1. i-affection: Short *e and *o are raised to i and u when the following syllable contains a high vowel (*i, *ī, *u, *ū). It does not happen when the vowels are separated by certain consonant groups.
2. a-affection: Short *i and *u are lowered to e and o when the following syllable contains a non-high back vowel (*a, *ā, *o, *ō).
3. u-affection: Short *a, *e, *i are broken to short diphthongs au, eu, iu when the following syllable contains a *u or *ū that was later lost. It is assumed that at the point the change operated, u-vowels that were later lost were short *u while those that remain were long *ū. The change operates after i-affection so original *e may end up as iu.

Nominal examples (reconstructed forms are Primitive Irish unless otherwise indicated):

• sen "old (nominative singular)" < *senos, but sin "old (genitive singular)" < *senī (i-affection), siun "old (dative singular)" < *senu (i-affection and u-affection) < *senū < PIE *senōi, sinu "old (accusative plural)" < *senūs (i-affection but no u-affection because u remains) < PIE *senons.
• fer "man (nominative singular)" < *wiros (a-affection), but fir "man (genitive singular)" < *wirī (no a-affection), fiur "man (dative singular)" < *wiru (u-affection) < *wirū < PIE *wirōi, firu "men (accusative plural)" < *wirūs (no u-affection because the u remains) < PIE *wirons.
• nert "strength (nominative singular)", but neurt "strength (dative singular)" < *nertu (u-affection but no i-affection, which was blocked by the cluster rt) < *nertū < PIE *nertōi.
• mil "honey" (i-affection) < PCelt *meli, milis "sweet" < *melissos (i-affection).
• fiurt "miracle (nominative singular)" < *wirtus (u-affection; from Latin virtus), fert(a)e "miracle (nominative plural)" < *wirtowes.

Verbal paradigm example:

	form	Pronunciation	Meaning	Prim Irish	Post-PIE	Comments
Absolute 1sg	biru	/bʲiru/	"I carry"	*berūs	*bʰerō + -s	i-affection
Absolute 2sg	biri	/bʲirʲi/	"you (sg.) carry"	*berisis	*bʰeresi + -s	i-affection (unstressed *-es- > *-is- in Primitive Irish, also found in s-stems)
Absolute 3sg	berith	/bʲirʲəθʲ/	"he carries"	*beretis	*bʰereti + -s	Unstressed i = /ə/ with surrounding palatalised consonants; see #Orthography
Conjunct 1sg	·biur	/bʲĭŭr/	"I carry"	*beru < *berū	*bʰerō	i-affection + u-affection
Conjunct 2sg	bir	/bʲirʲ/	"you (sg.) carry"	*beris < *berisi	*bʰeresi	i-affection (unstressed *-es- > *-is- in Primitive Irish)
Conjunct 3sg	beir	/bʲerʲ/	"he carries"	*beret < *bereti	*bʰereti	i in ei signals palatalisation of following consonant; see #Orthography

The result of i-affection and a-affection is that it is often impossible to distinguish whether the root vowel was originally *e or *i (sen < *senos and fer < *wiros have identical declensions). However, note the cases of nert vs. fiurt above for which i-affection, but not a-affection, was blocked by an intervening rt.

Proto-Celtic long vowels and diphthongs

Proto-Celtic long vowels and diphthongs develop in stressed syllables as follows:

Proto-Celtic	archaic Old Irish	later Old Irish	Example(s)
*ī	í		rí (gen. ríg) "king" (cf. Latin rēx, Sanskrit rājan-) rím "number" (cf. Old English rīm, Latin rītus "rite")
*ā	á		máthir "mother" (cf. Latin māter) dán "gift" (cf. Latin dōnum)
*ū	ú		cúl "back" (cf. Latin cūlus "ass, buttocks")
*ai	/ai/ (spelled áe or aí)	merged (both spellings used)	cáech "one-eyed" < PC *kaikos < PIE *keh₂i-ko- (cf. Latin caecus "blind", Gothic háihs "one-eyed")
*oi	/oi/ (spelled óe or oí)		oín, óen "one" < PIE *oinos (cf. archaic Latin oenos)
*ei > ē	é	ía	·tíagat "they go" < archaic ·tégot < PIE *steigʰ- (cf. Ancient Greek steíkhein "to walk", Gothic steigan ‘to go up’)
*au (+C) > ō	ó	úa	úaithed, úathad "singleness" < PC *autīto- < IE *h₂eu "again" + *to- "that" (cf. Ancient Greek autós "self")
*eu/ou (+C) > ō			núa, núë "new" < archaic núae < PC *noujos (cf. Gaulish novios) < IE *neu-io-s (cf. Gothic niujis) túath "tribe, people" < PC *toutā < IE *teutā (cf. Gothic þiuda) rúad "red" < PC *roudos < PIE *h₁reudʰ- (cf. Gothic rauþs)
*au (not +C)	áu	ó	ó "ear" < archaic áu, aue < PC *ausos < IE *h₂eus- (cf. Latin auris) nó "ship" < archaic náu < PC *nāwā < PIE *neh₂u- (cf. Latin nāvis)
*ou (not +C)	óu > áu		bó ‘cow’ < archaic báu < early archaic bóu (c. a.d. 700) < PC *bowos (gen.sg.) < PIE *gʷh₃-eu-

The Old Irish diphthongs úi, éu, íu stem from earlier sequences of short vowels separated by *w, e.g. drúid- "druid" < *dru-wid- "tree-knower".

Most instances of é and ó in nonarchaic Old Irish are due to compensatory lengthening of short vowels before lost consonants or to the merging of two short vowels in hiatus: cét /kʲeːd/ ‘hundred’ < Proto-Celtic kantom (cf. Welsh cant) < PIE *kṃtóm.

PIE consonants

Overview

See Proto-Celtic for various changes that occurred in all the Celtic languages, but these are the most important:

• PIE *gʷ > Proto-Celtic *b (but PIE *gʷʰ > *gʷ).
• Loss of aspiration in *bʰ *dʰ *gʰ *gʷʰ.
• Loss of *p. Initially and intervocalically it was simply deleted; elsewhere, it variously became *w, *b, *x etc.

From Proto-Celtic to Old Irish, the most important changes are these:

• Lenition and palatalisation, multiplying the entire set of consonants by 4. See #History for more details.
• Loss of most final consonants. See #Syncope in detail.
• Proto-Celtic *s is lenited to /h/, which then disappears between vowels. In general, Old Irish s when not word-initial stems from earlier geminate ss (often still written as such, especially in archaic sources).
• Proto-Celtic *kʷ *gʷ remain in Ogam Irish (maqqi "son" (gen. sg.)) but become simple c g in Old Irish. Occasionally, they leave their mark by rounding the following vowel.
• Proto-Celtic *w is lost early on between vowels, followed by early hiatus resolution. In some cases, *w combines with a preceding vowel to form a diphthong: béu béo "living, alive" < *bewas < *biwos < *gʷih₃uós. Other instances of *w become [β], which still remains in Ogam Irish. By Old Irish times, this becomes f- initially (e.g. fer "man" < *wiros, flaith "lordship" < *wlātis), lenited b after lenited voiced sounds (e.g. tarb "bull" < *tarwos, fedb "widow" < *widwā), f after lenited *s (lenited fïur "sister" < *swesōr), and is lost otherwise (e.g. dáu "two" < *dwōu, unlenited sïur "sister" < *swesōr).
• Proto-Celtic *y becomes *iy after a consonant, much as in Latin. The vowel *i often survives before a lost final vowel, partly indicating the nature of the final vowel as a result of vowel affection: cride cridi cridiu "heart" (nom. gen. dat.) < *kridion *kridiī *kridiū < *kridiyom *kridiyī *kridiyū < PIE *ḱr̥d- (e.g. gen. *ḱr̥d-és). After this, *y is lost everywhere (after palatalising a preceding consonant).

Initial clusters

Old Irish preserves, intact, most initial clusters unlike many other Indo-European languages.

Preserved initial clusters:

• sn- sm- sr- sl- sc- scr- scl-, e.g. snám "swimming", smiur "marrow", sruth "stream", scáth "shadow, reflection", scrissid "he scratches (out)", scléo "misery (?)".
• cr- cl- cn-, e.g. crú "blood", cloth "fame", cnú "nut".
• gr- gl- gn-, e.g. grían "sun", glé "clear", gnáth "customary".
• tr- tl- tn-, e.g. tromm "heavy', tlacht "garment", tnúth "jealousy, passion".
• dr- dl-, e.g. dringid "he climbs", dlong(a)id "he cleaves".
• mr- ml-, e.g. mruig "land", mliuchtae "milch".
• br- bl-, e.g. brú "belly", bláth "flower".

Modified initial clusters:

• *wl- *wr- > fl- fr-, e.g. flaith "lordship" < *wlātis, froích "heather" < *wroikos.
• *sp-/*sw- > s- (lenited f-), e.g. sïur "sister" (lenited fïur) < *suior < PIE *swesōr.
• *st- > t-, e.g. tíagu "I go" < *stēgū-s < post-IE *steigʰō.
• *pl- *pr- lose the *p.
• PIE *gʷn- > Proto-Celtic *bn- > mn-, e.g. mná "woman" (gen. sg.) < *bnās < PIE *gʷneh₂s, an extremely archaic noun form.

Intervocalic clusters

Many intervocalic clusters are reduced, becoming either a geminate consonant or a simple consonant with compensatory lengthening of the previous vowel. During the Old Irish period, geminates are reduced to simple consonants, occurring earliest when adjacent to a consonant. By the end of the Old Irish period, written ll mm nn rr are repurposed to indicate the non-lenited sounds /L m N R/ when occurring after a vowel and not before a consonant.

Cluster reduction involving *n:

• *nt *nk > unlenited /d g/ (normally written t c). Note that PCelt *ant,*ent > *ent > /eːd/ but *int *ont *unt > /idd odd udd/ like *nk: cét /kʲeːd/ "hundred" < PCelt *kantom (cf. Welsh cant) < PIE *kṃtóm; sét /sʲeːd/ "way" < *sentu- (vs. Breton hent); ro·icc, ric(c) /r(o)-iɡɡ/ "he reaches" < *ro-ink- (vs. Bret rankout "must, owe"); tocad /toɡað/ "luck" (vs. Bret tonkad "fate").
• *ns > unlenited s with compensatory lengthening of a preceding vowel; *ans > *ens > és similarly to *ant *ank: géis "swan" < PCelt *gansi- < PIE *ǵʰh₂ens- (vs. Dutch gans "goose").

Cluster reduction involving *s *z:

• Medial *sm *sn *sl > mm nn ll: am(m) "I am" < PIE *esmi.
• Medially, *st > ss (but *str > str, *rst > rt).
• *zb > db /ðv/, *zg > dg /ðɣ/ (but rg after an unstressed syllable), *zd > /dd/: net /nedd/ "nest" < PIE *nisdos /nizdos/.

Lenited stops *x *ɣ *θ *ð generally disappear before sonorants *r *l *n *m, with compensatory lengthening of the preceding vowel. Many examples occur in reduplicated preterites or words with consonant-final prefixes (such as ad-):

• du·air-chér "I have purchased" < *-xexr < PCelt *-kikra;
• ·cúal(a)e "he heard" < *koxlowe < PCelt *kuklowe;
• áram "number" < *að-rīm;
• ám thám "a moving to and fro" < *aɣm θ-aɣm (verbal nouns of agid "he drives" and compound do·aig);
• dál "assembly" < *daθl (cf. Old Welsh datl).

However, *θr, *βr, *βl survive: críathraid "he perforates" < PCelt *krētrāti-s; gabur "goat" < PCelt *gabros (cf. Welsh gafr); mebul "shame" (cf. Welsh mefl).

Grammar

Main article: Old Irish grammar

Old Irish is a fusional, nominative-accusative, and VSO language.

Nouns decline for 5 cases: nominative, accusative, genitive, prepositional, vocative; 3 genders: masculine, feminine, neuter; 3 numbers: singular, dual, plural. Adjectives agree with nouns in case, gender, and number. The prepositional case is called the dative by convention.

Verbs conjugate for 3 tenses: past, present, future; 3 aspects: simple, perfective, imperfective; 4 moods: indicative, subjunctive, conditional, imperative; 2 voices: active, and passive; independent, and dependent forms; and simple, and complex forms. Verbs display tense, aspect, mood, voice, and sometimes portmanteau forms through suffixes, or stem vowel changes for the former four. Proclitics form a verbal complex with the core verb, and the verbal complex is often preceded by preverbal particles such as ní (negative marker), in (interrogative marker), ro (perfective marker). Direct object personal pronouns are infixed between the preverb and the verbal stem. Verbs agree with their subject in person and number. A single verb can stand as an entire sentence. Emphatic particles such as -sa and -se are affixed to the end of the verb.

Prepositions inflect for person and number, and different prepositions govern different cases, sometimes depending on the semantics intended.

See also

• Early Irish literature
• Dictionary of the Irish Language
• Auraicept na n-Éces
• Goidelic substrate hypothesis

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• Sihler, Andrew (1995). New Comparative Grammar of Greek and Latin. Oxford University Press.CS1 maint: ref=harv (link)
• Stifter, David (2006). Sengoidelc: Old Irish for Beginners. Syracuse, New York: Syracuse University Press. ISBN 0-8156-3072-7.
• Strachan, John (1949). Old-Irish Paradigms and Selections from the Old-Irish Glosses. Revised by Osborn Bergin (Fourth ed.). Dublin: Royal Irish Academy. ISBN 0-901714-35-6.
• Thurneysen, Rudolf (1946). A Grammar of Old Irish. Translated by D. A. Binchy and Osborn Bergin. Dublin: Dublin Institute for Advanced Studies. ISBN 1-85500-161-6.CS1 maint: ref=harv (link)
• Tigges, Wim; Feargal Ó Béarra (2006). An Old Irish Primer. Nijmegen: Stichting Uitgeverij de Keltische Draak. ISBN 90-806863-5-2.

External links

• An Etymological Dictionary of the Gaelic Language MacBain, Alexander Gairm Publications, 1982
• Old Irish dictionary
• Old Irish Online by Patrizia de Bernardo Stempel and Jonathan Slocum, free online lessons at the Linguistics Research Center at the University of Texas at Austin
• eDIL (digital edition of the Dictionary of the Irish Language)