GNATHOSTOMA

‖Gna‐thos″to‐ma (?), n. pl. [[NL., from Gr. γνάθοσ the jaw + �, �, the mouth.]] (Zoöl.) A comprehensive division of vertebrates, including all that have distinct jaws, in contrast with the leptocardians and marsipobranchs (Cyclostoma), which lack them. [Written also Gnathostomata.]