/ˈamnēˌōt/
Noun, pl. amniotes
1. A group of tetrapods (four-limbed animals with backbones or spinal columns) that have an egg equipped with an amnios, an adaptation to lay eggs on land rather than in water as anamniotes do. (wikipedia.org)
2. Any of the Amniota group of vertebrates having an amnion during the development of the embryo; mammals, birds and reptiles. (wiktionary.org)
3. An animal whose embryo develops in an amnion and chorion and has an allantois; a mammal, bird, or reptile. (Google dictionary)