Irish Graphemic Module (LGM v1.0)


Irish Alphabet (Modern Latin-based)

Base Letters (18 core in native words)

Modern Irish uses 18 letters of the Latin alphabet for native vocabulary:
A, B, C, D, E, F, G, H, I, L, M, N, O, P, R, S, T, U

The remaining letters (J, K, Q, V, W, X, Y, Z) appear only in loanwords or foreign names.


Vowels

Irish distinguishes short and long vowels; long vowels are marked with the acute accent (fada).

GlyphLatin ChainPhoneme (IPA)Notes
Aa/a/short a
Áa + ´/aː/long a
Ee/ɛ/short e
Ée + ´/eː/long e
Ii/ɪ/short i
Íi + ´/iː/long i
Oo/ɔ/short o
Óo + ´/oː/long o
Uu/ʊ/short u
Úu + ´/uː/long u

Consonants & Broad/Slender Distinction

Irish consonants have two “flavors”:

  • Broad = followed by a, o, u → velarized (“dark”)
  • Slender = followed by e, i → palatalized (“light”)
GlyphLatin ChainPhoneme (broad)Phoneme (slender)
Bb/bˠ//bʲ/
Cc/kˠ//c/
Dd/dˠ//dʲ/
Ff/fˠ//fʲ/
Gg/ɡˠ//ɟ/
Hh/h//h/ (no broad/slender contrast)
Ll/l̪ˠ//lʲ/
Mm/mˠ//mʲ/
Nn/n̪ˠ//nʲ/
Pp/pˠ//pʲ/
Rr/ɾˠ//ɾʲ/ (trill/tap variation by dialect)
Ss/sˠ//ʃ/
Tt/t̪ˠ//tʲ/

Digraphs & Trigraphs (multi-letter graphemes)

  • bh/mh → /v/ (slender /vʲ/) or /w/ depending on context
  • dh/gh → voiced fricatives /ɣˠ/ (broad) or /j/ (slender)
  • ch → /x/ (broad) or /ç/ (slender)
  • fh → silent (historically /f/)
  • ph → /f/
  • sh/th → /h/
  • ng → /ŋ/ (before consonant) or /ŋɡ/ (before vowel)

System Notes for Lattice Integration

  • Irish orthography encodes palatalization via adjacent vowel letters, not diacritics on consonants.
  • Lenition (softening) is marked with “h” after the consonant — this changes the sound completely (b → bh /v/, c → ch /x/, etc.).
  • Eclipsis (nasalization/voicing) is marked by prefixing a consonant — e.g., b → mb, c → gc.
  • For our lattice, both broad/slender and mutation type must be feature flags so the same letter can be recognized in its altered states.