cloaca

noun5

1. •
   The opening in reptiles, amphibians and birds, as well as elasmobranchians, lobe-finned fishes, and monotreme mammals, which serves as the common outlet for the urogenital ducts and rectum.

   • In birds the rectum, at the termination of its canal, forms an oval or elongated pouch […] and then expands into a cavity, which has been named cloaca. — 1822
2. •
   Structure in the embryo during the development of the reproductive and urinary systems.
3. •
   (figurative) A sewer.

   • […] that tremendous cloaca of Pauperism […]
4. •
   An outhouse or lavatory.

   • To every house […] a cloaca. — 1840
5. •
   A duct through which gangrenous material escapes a body.

   • Across this shell [sc. of bone] small holes are eaten, by which the matter escapes, and which are called cloacae (Weidmann). — 1846