Nassa \Nas"sa\, n.; pl. E. {Nassas}, L. {Nassae}. [From L. nassa a kind of basket, in allusion to the reticulation of some species.] (Zool.) Any species of marine gastropods, of the genera {Nassa}, {Tritia}, and other allied genera of the family {Nassidae}; a dog whelk. See Illust. under {Gastropoda}. [1913 Webster] -- {nas"soid}, a. [1913 Webster]