Hawaiian phonology

The phonological system of the Hawaiian language is based on documentation from those who developed the Hawaiian alphabet during the 1820s as well as scholarly research conducted by lexicographers and linguists from 1949 to present.

Hawaiian is known for having only eight consonant phonemes: /p, k ⁓ t, ʔ, h, m, n, l ⁓ ɾ, w ⁓ v/. There is allophonic variation of [k] with [t], [w] with [v], and [l] with [ɾ]. The [t]–[k] variation is highly unusual among the world's languages.

Hawaiian has either 5 or 25 vowel phonemes, depending on how long vowels and diphthongs are analyzed. If the long vowels and diphthongs are treated as two-phoneme sequences, the total of vowel phonemes is five. However, if the long vowels and diphthongs are treated as separate, unit phonemes, there are 25 vowel phonemes. The short vowel phonemes are /u, i, o, e, a/. If long vowels are counted separately, they are /uː, iː, oː, eː, aː/. If diphthongs are counted separately, they are /iu, ou, oi, eu, ei, au, ai, ao, ae, oːu, eːi, aːu, aːi, aːo, aːe/. There is some allophonic variation of the vowels, but it is much less dramatic than that of the consonants.

Hawaiian syllable structure is (C)V(V) where C is any consonant and V is any vowel. Double vowels (VV) may be long vowels or diphthongs. All CV(V) syllables occur except for wū, but wu occurs only in two words borrowed from English. Word stress is predictable in words of one to four syllables but not in words of five or more syllables. Phonological processes in Hawaiian include palatalization and deletion of consonants and the raising, diphthongization, deletion, and compensatory lengthening of vowels. Phonological reduction (or "decay") of consonant phonemes during the historical development of Hawaiian has resulted in the phonemic glottal stop. The ultimate loss (deletion) of intervocalic consonant phonemes has resulted in long vowels and diphthongs.

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