Diapsida

plural noun

Di·​ap·​si·​da

dīˈapsədə

in some classifications

: a subclass of reptiles having two pairs of temporal openings in the skull and including the extinct dinosaurs and pterosaurs, the crocodiles and rhynchocephalians, and usually the lizards and snakes compare parapsida

diapsidan

(ˈ)dī¦apsədᵊn

adjective or noun

Word History

Etymology

New Latin, from di- + -apsida (from Greek hapsid-, hapsis arch, loop)

Love words?

You must — there are over 200,000 words in our free online dictionary, but you are looking for one that’s only in the Merriam-Webster Unabridged Dictionary.

Start your free trial today and get unlimited access to America's largest dictionary, with:

• More than 250,000 words that aren't in our free dictionary
• Expanded definitions, etymologies, and usage notes
• Advanced search features
• Ad free!