clo·a·ca (klō-āˈkə)

1. In early embryos, the entodermally lined chamber into which the hindgut and allantois empty.
2. The common cavity into which the intestinal, genital, and urinary tracts open in vertebrates such as fish, reptiles, birds, and some mammals.
3. An opening in a diseased bone containing a fragment of dead bone.

Related Forms:

• clo·aˈcal (-kəl) adjective