Geni*ti"val*ly

from The Collaborative International Dictionary of English v.0.48

Genitival \Gen`i*ti"val\, a.
   Possessing genitive from; pertaining to, or derived from, the
   genitive case; as, a genitival adverb. -- {Gen`i*ti"val*ly},
   adv.
   [1913 Webster]