Synapsid

Pronunciation

• UK IPA: /sɪˈnapsɪd/

Origin

Modern Latin Synapsida, from syn- + Ancient Greek ἁψίς ("arch").

Full definition of synapsid

Adjective

1. Pertaining to the class Synapsida, of animals which have an opening low in the skull roof behind each eye, leaving a bony arch beneath each.
• 1999, Matt Ridley, Genome, Harper Perennial 2000, p. 26:We are synapsid tetrapods, a group of reptiles that almost went extinct 200 million years ago in competition with the better-designed dinosaurs.

Noun

1. Any animal (including all mammals) of the class Synapsida.