Synapsida

plural noun
Syn·ap·si·da | \-psədə\

Definition of Synapsida 

: a subclass of Reptilia comprising extinct reptiles of the Pennsylvanian, Permian, and Triassic, having a single pair of lateral temporal openings in the skull, and usually held to be ancestral to the true mammals — compare ictidosauria , therapsida

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History and Etymology for Synapsida

New Latin, from synapsis + -ida

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Dictionary Entries near Synapsida

synaposematism

synapse

synapsid

Synapsida

synapsis

synapte

synaptic

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