Im*par"i*syl*lab"ic (?), a. [L. impar unequal + E. syllabic: cf. F. imparisyllabique.] Gram.
Not consisting of an equal number of syllables; as, an imparisyllabic noun, one which has not the same number of syllables in all the cases; as, lapis, lapidis; mens, mentis.
© Webster 1913.