plural noun

: an order of extinct insects related to the Ephemeroptera, known only from the Upper Carboniferous, and characterized by long cerci and homonomous wings with numerous crossveins

Word History


New Latin, from prot- + Ephemerida

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Dictionary Entries Near Protephemerida

Cite this Entry

“Protephemerida.” Dictionary, Merriam-Webster, Accessed 4 Dec. 2023.

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