Old Irish/Guide to Old Irish spelling
Old (and Middle) Irish spelling is fairly non-intuitive to Modern Irish speakers, below are some guidelines to help one understand it a bit better.
Consonants and marking lenition or lack of lenition
Old Irish orthography was based on Latin – as it was learnt by the Gaels from the Brythonic people – and British Latin pronunciation of that time had underwent basically the same processes as Welsh. The spelling is unintuitive to Modern Irish speakers, as it is based on Brythonic lenition patterns.
- The spelling of initial consonants is easy – since initial consonants weren’t generally lenited (except for grammatical initial mutations), they are read as generally expected in Latin-based writing systems, initial b, d, g, p, t, c and m denote /b, d, ɡ, p, t, k, m/ respectively.
- Irish lenition of voiceless /p, t, k/ is marked, as today, by h after them – ph, th, ch: ‘her cat’ is a catt /a ˈkat/ but ‘his cat’ is a chatt /a ˈxat/.
- The consonants between vowels (and liquids like n, r, l, and in coda after a vowel) are to be read as if they were lenited in Welsh, that means:
- b, d, g, m in the middle of a word are just lenited to /β, ð, ɣ, β̃/: the word rígain ‘queen’ is read /r´iːɣən´/, g between vowels denotes lenited /ɣ/ – hence modern Irish banríon, pre-reform (ban)ríoghan,
- p, t, c are voiced /b, d, ɡ/: the word póc is read /poːɡ/ and gives modern póg,
- medial /m/ and voiceless /p, t, k/ are often written doubled, so lomm /lom/ ‘bare, naked, exact’, peccad /p´ekəð/ ‘sin’, macc /mak/ for ‘son’, catt /kat/ for ‘cat’, etc. – but this is hardly consistent, often it’s ambiguous if some final or medial c means /ɡ/ or /k/ (and it’s more consistent in the middle of the word than word-finally), for example the word for ‘small’ is often written as becc with double cc even though it’s to be red /b´eɡ/ (modern beag).
Note: there is no way to mark lenition of initial voiced /b, d, ɡ, m/ – ‘his mother’ ⁊ ‘her mother’ are generally both a máth(a)ir – it’s either /a ˈmaːθər´/ or /a ˈβ̃aːθər´/ depending on meaning. But lenition of voiceless stops is marked consistently. And we know the voiced ones were lenited in the same positions from metrical clues (alliteration, rhyming, etc.).
The doubled non-lenited mm, ll, rr, nn are sometimes also written initially after unstressed words (like a ‘his, her’), so a mmáthair is unambiguously /a ˈmaːθər´/ ‘her/their mother’ (but can be written a máthair too) – spelt as if it were a single word.
Lenited s and f are often written ṡ /h/, ḟ (no sound). The s from old *sw can also be lenited to /f/ written variously as f, ph, ṡ (so a fiur, a phiur, a ṡiur for /a ˈfi.ur/ ‘his sister’, from siur, siür /s´i.ur/).
These conventions are imo nicely presented by two forms of the name Patrick to be found in Old Irish – it was borrowed twice from Latin Patricius:
- first is the older Cothriche, Cothrige /koθ´r´əɣ´e/, which continues something like /kʷaθrixijah/ (which would be written something like *QAT(T)RIC(C)IAS in ogham) – the Gaels borrowed Latin /p/ as /kʷ/ as there was no native /p/ phoneme in Primitive Irish, and the medial voiceless /t, k/ were lenited to /θ, x/, the nominative ending /-ah/ fell out due to apocope before Old Irish,
- later Pátraic /paːdrəɡ´/ – notice t and c written like in Latin original but read voiced – that’s because it was borrowed in later times from British Latin with the Brythonic lenition, and this form is continued today in Irish Pádraig and Scottish Gaelic Pàdraig.
Old Irish spelling and pronunciation of vowels (and marking of slender consonants)
Old and Middle Irish manuscripts aren’t very consistent in the way they write vowels, so below is a bit idealized overview picture – modern normalized editions generally follow these conventions.
OIr. had slender/broad consonant distinction similar to modern Irish or Sc. Gaelic, but it didn’t use the modern slender-with-slender, broad-with-broad orthographic rule to mark them.
There were 5 non-reduced phonemic vowel qualities in OIr.: /a, o, u, e, i/ and they could be long or short – they were generally written down using their respective Latin alphabet characters. Long vowels either weren’t marked at all or had the acute accent (‘fada’) over them (á, ó, ú, é, í). OIr. also had quite a few diphthongs, more about them in a minute.
In stressed syllables any vowel quality or a diphthong could occur. In unstressed syllable in the absolute end of a word any short vowel (but not long or diphthong) could occur. But in unstressed syllables between two consonants you may find either a long vowel, an /u/, or a short vowel that is completely determined by the quality of the surrounding consonants. Because of that Kim McCone and David Stifter postulate only two medial unstressed short vowel phonemes for Old Irish: /u/ and /ə/.
Slender consonants in stressed syllables are followed by front vowels e or i (or diphthongs beginning in them), eg. ben /b´en/ ‘woman, wife’.
If in an unstressed syllable /u/ followed a slender consonant, it was written iu, eg. lé(i)ciud /L´eːɡ´uð/ ‘letting’. If the word ends in a broad vowel /a/ or /o/ following a slender consonant, e is inserted between them: ní·lé(i)cea /niːˈL´eːɡ´a/ ‘may (s)he not leave’ (pres. subj.).
Before a slender consonant often (especially in the end of a word) an additional i was written, hence benn /b´eN/ ‘peak, mountain’ (nom.sg.) vs beinn /b´eN´/ (acc.sg.) – but this was not consistent, especially medially (if the vowel following the consonant showed its quality), hence léiciud or léciud.
If /e/ or /i/ is the last vowel of a word, orthographical a might be added to mark the last consonant as broad, eg. daltae or dalte /daLte/ ‘fosterling’, daltai or dalti /daLti/ ‘fosterlings’.
If the last vowel is i or í followed by a consonant, it’s generally impossible to determine whether the consonant is broad or slender from orthography, eg. ríg can be either /R´iɣ´/ (eg. acc.sg. of rí ‘king’) or /R´iɣ/ (gen.sg.) depending on its grammatical function. (In modern Irish o is inserted in such case before broad consonants, eg. mionn from OIr. mind /m´iNd/ ‘diadem, insignia’.)
The ‘reduced vowel /ə/’ was written as:
- a between two broad consonants, eg. sacart /saɡəRt/ ‘priest’,
- i between two slender consonants, eg. beirid or berid /b´er´əð´/ ‘(s)he carries’,
- e between a slender and a broad consonant, Goídelc /ɡoːi̯ð´əlɡ/ ‘Gaelic, Old Irish’,
- ai or i between a broad and a slender consonant, eg. légaid or légid /L´eːɣəð´/ ‘(s)he reads’, máthair, máthir /maːθər´/ ‘mother’,
- o or u when standing next to bilabial consonant (perhaps pronounced /u/ then?): lebor, lebur, lebar /L´evər ~ L´evur/ ‘book’, Conchobar, Conchobor, Conchobur /konxəvər ~ konxuvur/ ‘Conchúr’.
Note that the spellings berid and légid are ambiguous (it’s not obvious if the r and g in them are slender or broad), thus in modern normalized spelling it’s common to use the unambiguous beirid and légaid.
Diphthongs and hiatus
Old Irish had ‘long’ diphthongs combining most vowels with either /i/ or /u/ – some of them merged early already in OIr. times, most merged eventually, and only ía and úa survived to modern day. The diphthongs are: The three i-diphthongs:
- /o(ː)i̯/ written óe (before broad consonant) or oí (before either broad or slender), eg. óen, oín /oːi̯n/ ‘one’, Goídelc /ɡoːi̯ð´əlɡ/ ‘Gaelic, Old Irish’,
- /a(ː)i̯/ written áe (before broad consonant) or aí (before broad or slender), eg. láech, laích /Laːi̯x/ ‘hero’, genitive laích /Laːi̯x´/ ‘hero’s, of hero’, máel, maíl /maːi̯l/ ‘shorn, bald’, cáera, caíra /kaːi̯ra/ ‘sheep’,
- /u(ː)i̯/ written uí, eg. druí /dRuːi̯/ ‘druid, draoi’,
/oːi̯/ and /aːi̯/ fell together fairly early, /uːi̯/ merged with them too, so you get spellings like lóech, móel, draí too. In Classical Gaelic they all evolved into /ɯː/ written as ao ~ áo and evolved differently in later languages, hence in modern languages aon, laoch, laoich, maol, caora, draoi(dh).
- /eːu̯/ written éu or éo, eg. béu, béo /b´eːu̯/ ‘alive’, á éunu /aː ˈeːu̯nu/ ‘o birds’ (vocative pl.), céol, céul /k´eːu̯l/ ‘music’,
- /iːu̯/ written íu, eg. indíu /iN´d´iːu̯/ ‘today’, cíuil /k´i:u̯l´/ ‘of music’ (gen.sg.),
- /oːu̯, aːu̯/ written respectively óu and áo, áu, eg. bóu ‘of a cow’ (gen.sg. of bó) and báo, báu ‘of cows’ (gen.pl.) – these merged early with ó, so the gen.sg. and gen.pl. both occur as just bó too,
The first two of them later moved towards long /(ʲ)oː/ and /u/ respectively, hence modern beo, beò /b´oː, bjoː/, ceol, ceòl /k´oːl/, inniu, an-diugh /əˈN´u(v), əN´ˈd´u/.
and the two a-diphthongs which appeared from breaking of older *ē, *ō before broad consonants, they survived to this day:
- /iːa̯/ written ía, eg. grían /g´R´iːa̯n/ ‘sun’ (from earlier *grēna, cf. gen.sg. gréine /g´R´eːn´e/),
- /uːa̯/ written úa, eg. trúag /tRuːa̯ɣ/ ‘sad’.
Note the placement of the ‘fada’ – in manuscripts the length mark could be written on either vowel, or not written at all (so maíl, mael, maél, or láech, laich, láich, laích, loech, lóech, etc. all are forms you can find written) – but modern editors generally place the length mark on the first vowel, except for diphthongs with i when the í always gets the ‘fada’. That’s to avoid ambiguity with i used to mark slenderization, compare eg. póice /poːɡ´e/ ‘of a kiss’ (gen.sg. of póc) without a diphthong with Goídelc /ɡoːi̯ð´əlɡ/.
Also stressed short vowels /i, a, e/ could merge with /u/ to form short diphthongs:
- /iu̯/ written iu, eg. fiur /f´iu̯r/ ‘man’ (dat.sg.),
- /au̯/ written au, eg. baullu /bau̯Lu/ ‘members’ (acc.pl. of ball /baL/) – this early merged with /u/, hence also bullu /buLu/,
- /eu̯/ written eu, eo, eg. (dond) euch, eoch /eu̯x/ ‘(to the) horse’ (dat.sg. of ech /ex/).
But OIr. also allowed hiatus, ie. two syllabic vowels standing next to each other, and most commonly two consecutive vowel signs next to each other mean that. In modern editions often diaeresis (¨) is placed over the second one in this case, eg. fiach, fiäch /f´i.əx/ ‘raven’, siur, siür /s´i.ur/ ‘sister’, early óac, óäc /oː.əɡ/ ‘young’ (later óc /oːɡ/), early druï /dRu.i/ (→ druí). Hiatus generally merged with long diphthongs in Ireland before MIr. but it stayed sometimes in Sc. Gaelic, hence eg. modern Sc. G. fitheach /fi.əx/, piuthar /pju.ər/ vs Irish fiach /f´iːəx/, siúr /ʃuːr/.
Note that when no diaeresis is written, the spelling can be ambiguous, esp. if the second element is u, eg. fiur can mean either monosyllabic /f´iu̯r/ (‘man’, dat.sg.) or disyllabic /f´i.ur/ (‘sister’, lenited siür). In unstressed syllable Ciu means /C´u/, as mentioned in 1st post above (léiciud /L´eːɡ´uð/).
- most often the first syllable of the word, or in case of compound verbs commonly the second syllable – first after the first prefix (in modern normalized spelling often marked with a mid-high dot, eg. as·beir /asˈb´er´/)
- because the medial unstressed vowel is so consistently written, phonemic transcription for OIr. on Wiktionary doesn’t use the /ə/ character and instead transcribes their full quality, eg. sacart is [ˈsaɡar͈t], beirid is [ˈbʲerʲiðʲ], légaid is /ˈl͈ʲeɣiðʲ/ – Wiktionary here often (but not consistently) uses square brackets  to mark it’s a “surface-phonemic” transcription, ie. it shows the surface value of the vowels even if phonologically you can treat all those vowels as a single /ə/; note that to get Stifter’s transcription it’s sufficient to change all non-u short unstressed vowels followed by a consonant to /ə/; and vice versa, to restore the ‘surface’ vowel, enough to change /ə/ to the corresponding written one
- something weird happened with this diphthong/vowel in the word Goídelc, it was regularly Gáoidhealg, Gaoidhealg /ɡɯːð´əlɡ ~ ɡɯːɣ´əlɡ/ in Classical Gaelic, but later evolved (irregularly?) into Gaeilg, Gàidhlig, Gaelg/Gailck
- with /pj-/ instead of /ʃ-/ by analogical delenition of /f´-/ in the OIr. lenited form fiür /f´i.ur/ (see the next footnote) as if from *piür, *phiür
- this lenition of /s´/ to /f´/ happens because in earlier language this word had /sw-/ (cf. eg. German Schwester) which lenited first to /hw/ and later yielded /f/