plural noun
Sphe·​nac·​odon·​tia | \ -ntēə\

Definition of Sphenacodontia

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

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History and Etymology for Sphenacodontia

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

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