Definition of: uterus

(y′tər·əs) noun plural u·ter·i (y′tər·ī)
1. Anat. The organ of a female mammal in which the young are protected and developed before birth; the womb. In the higher mammals the uterus is single, but in the lower, as marsupials and monotremes, it is double.
2. Zool. Any differentiated portion of an oviduct found in various animals, other than mammals, serving as a repository for the development and nourishment of the eggs or the young during the embryonic stage. [<L]