disimilación

Dissimilation is a phonological process in which two neighboring or nearby sounds become less similar to one another. It operates to increase perceptual distinctiveness or to simplify articulation, and it can affect consonants, vowels, or a combination of segments.

The phenomenon can be described as regressive (anticipatory) dissimilation, where a sound changes to be less like a preceding one, or progressive dissimilation, where a sound changes to be less like a following one. It can occur within a single word or across morpheme boundaries, and it is observed in many language families as a diachronic (historical) change as well as in synchronic (contemporary) phonology. Consonantal dissimilation is more commonly attested than vowel dissimilation, but both can occur. Triggers include a preference for varied articulatory features (place, manner, voicing) and the need to avoid awkward or indistinct sequences.

Across languages, dissimilation contributes to shaping phonotactics and word structure, sometimes creating new phonemes or altering existing ones. It may be regular within a system, or occur sporadically due to historical contact, analogy, or morphological reanalysis. Because it can obscure historical relationships, dissimilation is an important consideration in the reconstruction of proto-languages and in the study of language change.

See also: assimilation, elision, metathesis, epenthesis, phonotactics.