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Definition 2024

amniote ‎(plural amniotes)

(biology) Any of the Amniota group of vertebrates having an amnion during the development of the embryo; mammals, birds and reptiles.
- 2011, Richard Shelton, "Sheep, pig, whale", Times Literary Supplement, 22 Sep 2011:
  Natural selection responded accordingly and the ultimate result was not just the evolution of more amphibians but ultimately of creatures no longer dependent on an aquatic habitat for reproduction, the so-called amniotes – the animals we know today as reptiles, birds and mammals.

vertebrate having an amnion during the development of the embryo