The Collaborative International Dictionary
Genitival
Genitival \Gen`i*ti"val\,
Possessing genitive from; pertaining to, or derived from, the genitive case; as, a genitival adver
-- Gen`i*ti"val*ly, adv.
Douglas Harper's Etymology Dictionary
Wiktionary
genitival
a. Having genitive form; pertaining to, or derived from, the genitive case; as, a genitival adverb