dionym|ˈdaɪənɪm| [ad.Gr. διώνυµ-ος, -ον having two names, f. δι-, (di-2) twice + ὄνοµα name.] A name consisting of two terms (as the names in zoology or botany, the two terms of which denote respectively the genus and species). 18..Coues is cited by Cent.Dict.