Answer: allophones

AnswerCrossword Clue
ALLOPHONESLinguistic forms
allophonesAny of the speech sounds that represent a single phoneme, such as the aspirated k in kit and the unaspirated k in skit, which are allophones of the phoneme k
allophonesALLOPHONE, any of several speech sounds regarded as variants of a given phoneme