noun pl. cloacae -·cae′ (-sē′, -kē′) or cloacas -·cas

1. a sewer or cesspool
2. Zool.
   1. the cavity into which both the intestinal and the genitourinary tracts empty in reptiles, birds, amphibians, and many fishes
   2. in some invertebrates, a similar cavity serving as an excretory, respiratory, and reproductive duct

Etymology: L < cluere, to cleanse < IE base *lū-, to rinse, clean > Gr klyzein, to wash, Ger lauter, pure