plural noun

: an order of extinct insects of the Upper Carboniferous and Permian that are related to the mayflies and dragonflies and have extremely long cerci

Word History


New Latin, probably from mega- + Greek sēkos pen, fold, trunk of a tree + New Latin -ptera

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Dictionary Entries Near Megasecoptera

Cite this Entry

“Megasecoptera.” Dictionary, Merriam-Webster, Accessed 19 Jul. 2024.

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