Allophonic as an adjective is of or pertaining to an allophone. while Phoneme as a noun is an indivisible unit of sound in a given language. a phoneme is an abstraction of the physical speech sounds (phones) and may encompass several different phones.
Part of speech: adjective
Definition: Of or pertaining to an allophone.
Part of speech: noun
Definition: An indivisible unit of sound in a given language. A phoneme is an abstraction of the physical speech sounds (phones) and may encompass several different phones.
We hope you now know whether to use Allophonic or Phoneme in your sentence.