any vertebrate of the group Amniota, comprising the reptiles, birds, and mammals, characterized by having an amnion during the embryonic stage.
any vertebrate animal, such as a reptile, bird, or mammal, that possesses an amnion, chorion, and allantois during embryonic development Compare anamniote
Any of the vertebrates that have an amnion during embryonic development. Reptiles, birds, and mammals are amniotes.
- Amniotic cavity
amniotic cavity amniotic cavity n. The fluid-filled cavity surrounding the developing embryo.
- Amniotic fluid
the watery fluid in the amnion, in which the embryo is suspended. Contemporary Examples Chronic uncertainty surrounds children living under occupation like amniotic fluid. More on Palestinian Children Emily L. Hauser July 26, 2012 Historical Examples The constant presence of nutritive substances in the amniotic fluid during the whole period of gestation. Simon Magus George […]
- Amniotic fold
amniotic fold amniotic fold n. A fold of amniotic membrane enclosing the yolk stalk and extending from the point of insertion of the umbilical cord to the yolk sac.
- Amniotic sac