plural noun

: a suborder of Pelycosauria comprising primitive Permian reptiles that resemble mammals

Word History


New Latin, from Sphenacodont-, Sphenacodon, genus of reptiles (irregular from sphen- + -odont-, -odon) + -ia

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Dictionary Entries Near Sphenacodontia

Cite this Entry

“Sphenacodontia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Sphenacodontia. Accessed 17 Apr. 2024.

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