Navajo phonology

The phonology of Navajo is intimately connected to its morphology. For example, the entire range of contrastive consonants is found only at the beginning of word stems. In stem-final position and in prefixes, the number of contrasts is drastically reduced. Similarly, vowel contrasts (including their prosodic combinatory possibilities) found outside of the stem are significantly neutralized.

Like most Athabascan languages, Navajo is coronal heavy, having many phonological contrasts at coronal places of articulation and less at other places. Also typical of the family, Navajo has a limited number of labial sounds, both in terms of its phonemic inventory and in their occurrence in actual lexical items and displays of consonant harmony.

The consonant phonemes of Navajo are listed below.

All consonants are long, compared to English: with plain stops the hold is longer, with aspirated stops the aspiration is longer, and with affricates the frication is longer. The voice onset time of the aspirated and ejective stops is twice as long as that found in most non-Athabaskan languages. Young & Morgan (1987) described Navajo consonants as "doubled" between vowels, but in fact they are equally long in all positions.

All stops and affricates, except for the bilabial and glottal, have a three-way laryngeal contrast between unaspirated, aspirated, and ejective. The labials /p, m/ are found in only a few words. Most of the contrasts in the inventory lie within coronal territory at the alveolar and palatoalveolar places of articulation.

The aspirated stops /tʰ, kʰ/ (orthographic ⟨t⟩, ⟨k⟩) are typically aspirated with velar frication [tx, kx] (they are phonetically affricates — homorganic in the case of [kx], heterorganic in the case of [tx]). The velar aspiration is also found on a labialized velar [kxʷ] (orthographic ⟨kw⟩). There is variation within Navajo, however, in this respect: some dialects lack strong velar frication having instead a period of aspiration.

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