[am-nee-oht] 
| any vertebrate of the group Amniota, comprising the reptiles, birds, and mammals, characterized by having an amnion during the embryonic stage. |
| am·ni·ote (ām'nē-ōt') n. Any of a group of vertebrates that have an amnion during embryonic development, including reptiles, birds, and mammals. [From New Latin amniōta, amniotes, from Greek amniōn, amnion (influenced by amniotic).] |
amniote
a group of limbed vertebrates that includes all living reptiles (class Reptilia), birds (class Aves), mammals (class Mammalia), and their extinct relatives and ancestors. The amniotes are the evolutionary branch (clade) of the tetrapods (superclass Tetrapoda) in which the embryo develops within a set of protective extra-embryonic membranes-the amnion, chorion, and allantois.
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niˌoʊt