Found:

diacritic feature

MORPHOLOGY: a formal expression of unpredictable information about words in their lexical entry. EXAMPLE: many non-native English verbs may undergo -ation and/or -al affixation (recite: recital: recitation). However, the verbs arrive and derive do not allow the derivation of *arrivation and *derival, respectively. Halle (1973) accounts for these accidental gaps by assigning the diacritic feature [-lexical insertion] to these forms. Other widely used diacritic features are [+/- latinate] or [+/- native] (e.g. Aronoff 1976). Another term is exception feature.

LIT.	Aronoff, M. (1976) Chomsky, N. and M. Halle (1968) Halle, M. (1973) Spencer, A. (1991)