plural noun
Pa·​rap·​si·​da | \ pəˈrapsədə \

Definition of Parapsida

in some classifications
: a subclass of reptiles in which the skull has two dorsal temporal openings adjoining the parietals and which includes the ichthyosaurs and related extinct forms and sometimes the lizards and snakes — compare diapsida

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!

History and Etymology for Parapsida

New Latin, from para- entry 1 + -apsida (from Greek hapsid-, hapsis arch, loop)

Keep scrolling for more

Learn More about Parapsida

Statistics for Parapsida

Cite this Entry

“Parapsida.” Dictionary, Merriam-Webster, Accessed 26 Feb. 2021.

Style: MLA
MLA Chicago APA Merriam-Webster

Comments on Parapsida

What made you want to look up Parapsida? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

February 2021 Words of the Day Quiz

  • squirrel in winter
  • Which is a synonym of perdure?
True or False

Test your knowledge - and maybe learn something along the way.


Anagram puzzles meet word search.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!