plural noun

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
adjective or noun

Word History


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

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Dictionary Entries Near Diapsida

Cite this Entry

“Diapsida.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Diapsida. Accessed 19 May. 2024.

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