Old-Irish Spelling and Pronunciation

by Dennis King

Reading Old Irish: The Values of the Letters

The challenge of reading Old Irish orthography can be briefly stated: all the letters representing consonants have multiple phonemic values. The pronunciation of a letter is determined mainly by its position in relation to other letters in the same word, and in the case of initial letters, by the influence of preceding words.


  1. Consonants: Slender and Broad
  2. Consonants: Voiced Stops
  3. Consonants: Unvoiced Stops
  4. Consonants following “R, L, N”
  5. Consonants: “F”
  6. Consonants: “S”
  7. Consonants: “R, L, N”
  8. Consonants: “H”
  9. The Vowels
  10. Word Stress
  11. Sample Text

1. Consonants: Slender and Broad

To begin with, every consonant, with the sole exception of “h”, has two variants, traditionally called “broad” and “slender”. The slender consonants differ from the broad ones in that they are palatalized, or end with a y-glide. As an example of the difference between them, in some dialects of English the word “tune” is pronounced with a broad “t”, so that it might be written “toon”, while in other dialects it is pronounced with a slender “t”, so that it might be written “tyoon”.

In Old Irish spelling, slender consonants are those that are followed by the letters “e” or “i”. If the consonant is in final position, it is slender if it is preceded by an “i”. All the consonants in these words are slender:

berid /b′er′ið′/carries
céle /k′eːl′e/companion, client
óir /oːr′/of gold

In these words only the letter “d” is slender:

buiden /buð′en/company
delb /d′elv/image
dét /d′eːd/tooth

Note that in phonological transcription, slender quality is shown by an apostrophe following the consonant.

2. Consonants: Voiced Stops

The letters “g, d, b” share certain orthographical strategies and therefore can be usefully discussed together. When these letters are in initial position, and not influenced by a preceding word, they represent voiced stops. The letter “m”, while usually classed as a nasal and not a voiced stop, behaves in many of the same ways and thus will be included here.

gort /gort/field
dún /duːn/fortress” [Note: /d/ is a dental stop, tongue against teeth]
mér /m′eːr/finger

When “g, d, b” are in non-initial position, they stand for the lenited equivalents of the voiced stops:

mug /muγ/slave
mod /moð/way; work
dub /duv/black
dam /daṽ/ox

If “b” or “m” is written double in non-initial position, however, it retains its voiced stop pronunciation:

abb /ab/abbot
lomm /lom/bare

When a word begins with the letters “g, d, b, m” the initial sound is subject to the mutation called lenition. This occurs under the influence of a preceding word. Lenition is not shown by any change in the spelling, however. For example, the masculine possessive pronoun “a” (= “his”) causes lenition:

a gort /a γort/his field
a dún /a ðuːn/his fortress
a bó /a voː/his cow
a mér /a ṽ′eːr/his finger

Note the pronunciations of the lenited sounds:

/γ/ = like a Spanish “g” between vowels
/ð/ = like the “th” in English “there”
/v/ [sometimes shown as β] = a bilabial “v” (made with both lips rather than the lower lip and the upper front teeth)
/ṽ/ [sometimes shown as a μ] = a bilabial “v” with nasalization of the following vowel

(Note that the lenited forms of “g, d, b, m” came to be written “gh, dh, bh, mh” in later Irish. Since these letter combinations were foreign to Latin, however, the writers of Old Irish apparently did not feel comfortable adopting them just yet. In any case, as native speakers of the language, they could usually automatically supply the lenited pronunciation from context.)

Words that begin with the letters “g, d, b” are also subject to another mutation called “eclipsis” or “nasalization”. When these letters are eclipsed, again due to the influence of a preceding word, the change is shown in the spelling by the addition of an “n” or “m”. The plural possessive pronoun “a” (= “their”) causes eclipsis:

a ngort /aŋ ort/their field” [/ŋ/ as in English “sing”]
a ndún /a Nuːn/their fortress
a mbó /a moː/their cow

3. Consonants: Unvoiced Stops

The letters “c, t, p”, likewise share certain orthographical conventions.

In intial position, these letters represent the unvoiced stops (which correspond to the voiced stops “g, d, b”) as follows:

tol /tol/will, wish” [Note: /t/ is a dental stop, tongue against teeth]
póc /poːg/kiss

In non-initial position, these letters stand for the corresponding voiced stops:

loc /Log/place
fot /fod/length
popul /pobul/people

(Note that in later Irish, this rule was jettisoned and the words above came to be spelled “log, fod, pobul”, or “log, fad, pobal” in Modern Irish.)

If “c, t, p” are doubled in non-initial position, however, they retain their unvoiced pronunciation:

macc /mak/son
att /at/swelling
sopp /sop/wisp

Words that begin with “c, t, p” are subject to both lenition and nasalizaton (eclipsis). Lenition is shown by a change in spelling:

a chú /a xuː/his hound” [x as the “ch” in “loch”]
a chenn /a x′eN/his head” [x′ (= /ç/) as the “ch” in German “ich”]
a thol /a þol/his will” [þ (usually shown as theta) as the “th” in English “thing”]
a phóc /a foːg/his kiss” [f as a bilabial /f/]

The digraphs “ch, th, ph” also appear, with the same pronunciation, in non-initial position as a permanent component of words:

ech /ex/horse
áth /aːþ/ford
oíph /oif/beauty

When “c, t, p” are eclipsed, however, their is no overt change in the spelling to indicate this mutation. When eclipsed, “c, t, p” are pronounced as their voiced equivalents:

a cú /a guː/their hound
a tol /a dol/their will
a póc /a boːg/their kiss

(Note that in Modern Irish eclipsis of “c, t, p” is shown by the addition of the appropriate consonant: “a gcú, a dtoil, a bpóg”.)

4. Consonants following “R, L, N”:

There is some ambiguity in the value of stop consonants following “r, l, n”. For example, “derc” may represent either /derg/ or /derc/, although it was fairly common for scribes to disambiguate them by writing the first as “derg” and the second as “derc”.

5. Consonants: “F”

The letter “f” represents a bilabial /f/, as in

fér /f′eːr/grass

When lenited, it is written “” with a dot over the letter, or in later spelling as “fh”, and its pronunciation is ‘zero’; that is to say, it vanishes entirely:

a fhér /a eːr/his grass

When “f” is eclipsed, it is pronounced as a bilabial “v”, but no change is made in the spelling:

a fér /a v′eːr/their grass

(The modern Irish spelling, however, is precise: “a bhféar”.)

6. Consonants: “S”

The letter “s” is pronounced as an English “s” when broad:

sacart /sagart/priest

And as an English “sh” when slender:

secht /s′ext/seven

When “s” is lenited, it is written “” with a dot over it, or in later spelling as “sh”, and is then pronounced /h/:

a shacart /a hagart/his priest

Words beginning with the letter “s” are not subject to eclipsis.

7. Consonants: “R, L, N”

When in initial position, or when doubled, these letters stand for tense varieties of “r, l, n”, sounds that have been preserved in some dialects of modern Irish and Scottish Gaelic. If you don’t know how to make these distinctions, you can probably safely ignore them.

rún /Ruːn/secret
corr /koR/crane
loc /Log/place
coll /koL/hazel
nert /N′ert/strength
tonn /toN/wave

In all other cases, or when lenited, the letters “r, l, n” are to be given a lax pronunciation:

cor /kor/putting
a rún /a ruːn/his secret
col /kol/sin
a loc /a log/his place
dán /daːn/poem, art, gift
a nert /a n′ert/his strength

Words beginning with “r, l, n” are not subject to eclipsis.

8. Consonants: “H”

The letter “h” was apparently mute in Insular Latin. When the scribes and scholars wrote Old Irish, they therefore felt free to add a mute “h” to the beginning of any word beginning with a vowel, especially if it was a puny little word like “i” (= in) that needed fattening up. From the evidence of Modern Irish and Scottish Gaelic, however, it seems likely that an “h” was in fact pronounced before vowels following certain words, such as “a” meaning “her”, so that “a ór” (= her gold) would have been pronounced /a hoːr/. The scribes, for their part, did not choose to show this /h/ in any consistent way. The practical outcome: the letter “h” by itself is meaningless in Old Irish texts, except as a member of the digraphs “ch, th, ph”.

9. The Vowels

Old Irish had five short vowels, “a, e, i, o, u” and five long vowels, “á, é, í, ó, ú”, which can be roughly said to have Latin or Continental values. There were two common diphthongs, one spelled variously “, áe, , ái” and the other “, óe, , ói”. These two sets ended up falling together, and can be pronounced either /oi/ or /ai/ as you wish. A third diphthong was “”, which can be pronounced as it is spelled. The real problem facing a modern reader of Old Irish is the fact that in digraphs such as “ai, ei, éi, ui, ái, ói, úi” the letter “i” may actually only serve to indicate the slender quality of the adjacent consonant. For example, “céle” is commonly written “céile”, with the “i” there simply to reinforce the slender value of the “l”. If in such cases the “i” is pronounced at all, it is only a light glide vowel.

10. Word Stress

Old Irish, like most dialects of Modern Irish and Scottish Gaelic, had a strong stress accent on the first syllable of nouns, adjectives and the absolute forms of verbs. Compound verbs are accented on the first syllable after the first preverb.

11. Sample Text

Manannán is speaking in this stanza from “Immram Brain”. This is the restored text according to Séamus Mac Mathúna, and my English. Below it are interlinear versions showing word for word translation and two styles of phonemic transcription. The second style, often called “newspaper phonetics”, is very inexact, but may have the virtue of allowing a novice to approach the sound and rhythm of the original.

Caíne amrae lasin mBran
ina churchán tar muir nglan;
os mé im charput do chéin,
is mag scothach imma-réid.
A marvelous beauty it seems to Bran
in his coracle across the clear sea;
For me, in my chariot from afar,
it’s a flowered plain he rides about.
ismaγskoþaxima reːð
issMAHGHSKO-thakhih-ma RAYTH (TH as in ‘then’)

Author: Dennis King, 1998-12-11
HTML: CPD, 1998-12-14