heteroclitic

adj

1. Irregular in inflection.
2. (Indo-European-studies)Signifying a nominal stem which alternates between more than one form when declined for grammatical case, particularly in the suffix (such as between *-r̥- in the strong stem and *-n̥- in the weak stem).

   “The Proto-Indo-European term *wódr̥ (“water”) is typical of nouns with heteroclitic stems: the strong stem *wódr̥- occurs in the direct cases while the weak stem *wédn̥- is found instead in the oblique cases, hence the contrast between nominative *wódr̥ and genitive *wédn̥s.”

3. Pertaining to antibodies that react to a wide variety of antigens.

   “[…] a heteroclitic response was never observed after the immunization with the deamidated peptide […]”

noun

1. A heteroclitic noun.