Biology .

a sudden departure from the parent type in one or more heritable characteristics, caused by a change in a gene or a chromosome.

an individual, species, or the like, resulting from such a departure.

the act or process of changing.

a change or alteration, as in form or nature.

Phonetics . umlaut.

Linguistics . (in Celtic languages) syntactically determined morphophonemic phenomena that affect initial sounds of words.

noun

inaction , stagnation

noun

alteration , anomaly , change , deviant , deviation , evolution , innovation , modification , mutant , novelty , permutation , transfiguration , transformation , variation , vicissitude , changeover , conversion , metamorphosis , shift , translation , transmogrification , transmutation , transubstantiation