See Also: synapsid(dictionary)

synapsid (iou)



synapsid adjective & noun. E20.
[from mod. Latin Synapsida (see below), formed as SYN- + Greek (h)apsid-, (h)apsis arch: see -ID3.]
A. adjective. Of or pertaining to the subclass Synapsida of extinct reptiles (considered close relatives of mammals) having a single temporal opening on each side of the skull, which were abundant in the late Permian and early Triassic and included pelycosaurs, therapsids, and cynodonts. E20.
b. noun. A reptile of the subclass Synapsida. Also called mammal-like reptile. E20.