Pronunciation: (u-nap'sid), [key]
belonging or pertaining to the Anapsida, a subclass of reptiles, extinct except for the turtles, characterized by having no opening in the temporal region of the skull.
a reptile of the subclass Anapsida. Cf. diapsid.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.