Consonants Middle Irish retained the Old Irish consonant inventory, though some assimilation and simplification of consonant clusters occurred. Stops were dropped when adjacent to /l/ or /n/, e.g. Old Irish
cland ("progeny") > Middle Irish
clann //. /ṽ/ lost its nasalisation before a vowel, e.g. Old Irish
memaid (s/he broke) // > Middle Irish
mebaid //, while /v/ was nasalised after nV, e.g. Old Irish
noeb ("saint") /noiv/ > Middle Irish
náem //. Initial /m/ was additionally
fortified to /b/ before liquids /r/ and /l/, e.g. Old Irish
mrath ̈(treachery) // > Middle Irish
brath //. :
Vowels During the Middle Irish Period, the nuclei of multisyllabic vowels shifted from those of Old Irish to the initial
secondary articulations of the succeeding syllable, e.g. Old Irish
duine ("person") /ˈdu.nʲe/ > */ˈduʲ.nʲe/ > Middle Irish /ˈdʷi.nʲe/. In interconsonantal /e/, this also involved a post-vocalic /ᵃ/ ephentesis, which briefly resulted in /CeᵃC/ before shifting to /CʲaC/, e.g. Old Irish
fer ("man") /fʲer/ > */fʲeᵃr/ > Middle Irish
fear /fʲar/. while the Old Irish diphthongs /ai/, /oi/, and /ui/ first shifted to */əi/, and were then monophongised to /əː/. In Ireland, a process of simplifying two vowels in
hiatus to a single long vowel occurred except for the late /ia(ː)/ and /ua(ː)/. In
Scottish Gaelic, hiatus were retained to the present. These processes created the following inventory of vowels and diphthongs: : ==Orthography==