plural noun Sphe·nac·odon·tia

Definition of Sphenacodontia

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

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Origin and Etymology of sphenacodontia

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

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a rounded knoll or a ridge of ice

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