High Quality Content by WIKIPEDIA articles! Navajo phonology is the study of how speech sounds pattern and interact with each other in that language. 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.