cloaca
noun
clo·a·ca klō-ˈā-kə 
plural cloacae klō-ˈā-ˌkē
-ˌsē
1
: sewer entry 3
2
a
[New Latin, from Latin] : the common chamber into which the intestinal and urogenital tracts discharge especially in monotreme mammals, birds, reptiles, amphibians, and elasmobranch fishes
also : a comparable chamber of an invertebrate
b
: the enlarged terminal part of the posterior embryonic digestive tract of a mammal that gives rise to the rectum, upper anal canal, and urogenital sinus
3
: cesspool sense 2
cloacal
klō-ˈā-kəl
adjective 
Example Sentences
Recent Examples on the Web Water snakes, like many snake species, will release a strong, musky odor from scent glands in their cloaca — an opening used for reproduction and excretion located near the base of the tail — when they are threatened or handled. 
Don Lyman, BostonGlobe.com, 13 July 2022 But a study published this year has offered experts their first detailed look at a dinosaur cloaca and its resemblance to the same setup in crocodiles. Riley Black, Smithsonian Magazine, 27 Dec. 2021 Comparisons to birds and crocodiles led experts to think that dinosaurs, too, had a single external opening called a cloaca. Riley Black, Smithsonian Magazine, 27 Dec. 2021 Males deposit little packets of sperm called spermatophores along the bottom of vernal pools, and females pick up the spermatophores in their cloaca, a multipurpose opening at the base of the tail that’s used for excretion and reproduction. BostonGlobe.com, 24 Mar. 2021 The cloaca was so well preserved that Vinther realized it could be reconstructed using 3-D computer modelling, reports Katherine J. Wu for the New York Times. Elizabeth Gamillo, Smithsonian Magazine, 21 Jan. 2021 The goal is to remove the oil gland and cloaca while also creating a hole to extract the innards. Natalie Krebs, Outdoor Life, 23 Dec. 2020 The team placed each bird in a small roosting enclosure near the campsite and inserted a tiny wire into their cloaca, an all-purpose hole that birds use to excrete waste, mate, and—in females—lay eggs. Lucy Hicks, Science | AAAS, 8 Sep. 2020 Estimating the height above ground and aperture of the cloaca—the opening through which penguins defecate—was equally simple. Jennifer Ouellette, Ars Technica, 4 July 2020 See More
Don Lyman, BostonGlobe.com, 13 July 2022 But a study published this year has offered experts their first detailed look at a dinosaur cloaca and its resemblance to the same setup in crocodiles. Riley Black, Smithsonian Magazine, 27 Dec. 2021 Comparisons to birds and crocodiles led experts to think that dinosaurs, too, had a single external opening called a cloaca. Riley Black, Smithsonian Magazine, 27 Dec. 2021 Males deposit little packets of sperm called spermatophores along the bottom of vernal pools, and females pick up the spermatophores in their cloaca, a multipurpose opening at the base of the tail that’s used for excretion and reproduction. BostonGlobe.com, 24 Mar. 2021 The cloaca was so well preserved that Vinther realized it could be reconstructed using 3-D computer modelling, reports Katherine J. Wu for the New York Times. Elizabeth Gamillo, Smithsonian Magazine, 21 Jan. 2021 The goal is to remove the oil gland and cloaca while also creating a hole to extract the innards. Natalie Krebs, Outdoor Life, 23 Dec. 2020 The team placed each bird in a small roosting enclosure near the campsite and inserted a tiny wire into their cloaca, an all-purpose hole that birds use to excrete waste, mate, and—in females—lay eggs. Lucy Hicks, Science | AAAS, 8 Sep. 2020 Estimating the height above ground and aperture of the cloaca—the opening through which penguins defecate—was equally simple. Jennifer Ouellette, Ars Technica, 4 July 2020 See More Word History
Etymology
Latin; akin to Greek klyzein to wash — more at clyster
First Known Use
circa 1656, in the meaning defined at sense 1
Medical Definition
cloaca
noun
clo·aca klō-ˈā-kə
plural cloacae -ˌkē, -ˌsē
1
a
: the common chamber into which the intestinal, urinary, and generative canals discharge especially in monotreme mammals, birds, reptiles, amphibians, and elasmobranch fishes
b
: the terminal part of the embryonic hindgut of a mammal before it divides into rectum, bladder, and genital precursors
2
: a passage in a bone leading to a cavity containing a sequestrum