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synapsid

Definitions of synapsid
  1. noun
    extinct reptile having a single pair of lateral temporal openings in the skull
    synonyms: synapsid reptile
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    types:
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    protomammal, therapsid
    probably warm-blooded; considered direct ancestor of mammals
    ictodosaur
    intermediate in form between the therapsids and most primitive true mammals
    pelycosaur
    large primitive reptile having a tall spinal sail; of the Permian or late Paleozoic in Europe and North America
    edaphosaurus
    heavy-bodied reptile with a dorsal sail or crest; of the late Paleozoic
    dimetrodon
    carnivorous dinosaur of the Permian in North America having a crest or dorsal sail
    Chronoperates paradoxus
    shrew-sized protomammal from the Alberta region of Canada; from about 55 million years ago (much more recent than other mammal-like reptiles)
    cynodont
    small carnivorous reptiles
    dicynodont
    a kind of therapsid
    type of:
    reptile, reptilian
    any cold-blooded vertebrate of the class Reptilia including tortoises, turtles, snakes, lizards, alligators, crocodiles, and extinct forms
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