• WordNet 3.6
    • n cloaca a waste pipe that carries away sewage or surface water
    • n cloaca (zoology) the cavity (in birds, reptiles, amphibians, most fish, and monotremes but not mammals) at the end of the digestive tract into which the intestinal, genital, and urinary tracts open
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Webster's Revised Unabridged Dictionary
    • Cloaca A privy.
    • Cloaca A sewer; as, the Cloaca Maxima of Rome.
    • Cloaca (Anat) The common chamber into which the intestinal, urinary, and generative canals discharge in birds, reptiles, amphibians, and many fishes.
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Century Dictionary and Cyclopedia
    • n cloaca An underground conduit for drainage; a common sewer: as, the cloaca maxima at Rome.
    • n cloaca A sink; a privy.
    • n cloaca [NL.] In zoology: In vertebrates, the enlarged termination of the rectum or lower bowel, forming a cavity originally in common with that of the allantois (in those animals which have an allantois) and permanently in common with the termination of the urogenital organs; the common chamber into which the intestine, ureters, sperm-ducts, and oviducts open, in sundry fishes, in reptiles and birds, and in the ornithodelphous mammals. This cavity is the common sewer of the body, receiving the refuse of digestion, the product of conception, the spermatic secretion, and the renal excretion, all to be discharged through the anal orifice. It is more or less incompletely divided into the cloaca proper, or the enlarged end of the rectum, and the urogenital sinus, a compartment in which terminate the ureters, sperm-ducts, and oviducts, and which contains the penis or clitoris when those organs are developed. There is no cloaca in adult mammals, with the exception of the monotremes, the separation of the urogenital sinus from the digestive tube being complete in all the others.
    • n cloaca In invertebrates, the homologous or analogous and corresponding structure effecting sewerage of the body: as in sponges, the common cavity in which the interstitial canal-systems open; in holothurians, the respiratory tree (which see, under respiratory).
    • n cloaca In entomology: A cavity found in many insects at the end of the abdomen, between the last dorsal and ventral segments, and receiving the extremity of the rectum. Also called the rectogenital chamber. The cæcum, or dilatation of the posterior end of the intestine.
    • n cloaca In ascidians, the common central cavity into which open the atrial chambers of all the ascidiozooids of an ascidiarium.
    • n cloaca [NL.] In pathology: In cases of necrosis, the opening in the sound bone which leads to the inclosed dead bone.
    • n cloaca The union of rectum, bladder, and organs of generation in a common outlet: a malformation resulting from arrest of development.
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Chambers's Twentieth Century Dictionary
    • n Cloaca klō-ā′ka a sewer: a privy: a cavity in birds and reptiles, in which the intestinal and urinary ducts terminate: a sink of moral filth
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Webster's Revised Unabridged Dictionary
Chambers's Twentieth Century Dictionary
L. cloācacluĕre, to purge.


In literature:

Wretched cloaca of a Book; without depth even as a cloaca!
"The French Revolution" by Thomas Carlyle
Only think of that cloaca being supplied daily with such dainty bibliographical treasures!
"Enemies of Books" by William Blades
Their mode of progression is backward, by the forcible ejection of a jet of water from an orifice in the neck, beside the rectum or cloaca.
"The Cruise of the Cachalot" by Frank T. Bullen
This great cloaca was the work of Tarquinius Superbus.
"Travels Through France and Italy" by Tobias Smollett
If the Cloaca is obstructed, give injections of Sweet Oil or Olive Oil with a small bulb syringe.
"The Veterinarian" by Chas. J. Korinek
He had discarded his first instinct, which was to hide in the intricate Tetrahyde cloaca.
"The Status Civilization" by Robert Sheckley
The Cloaca Maxima was formed of three tiers of arches, the vault within the innermost tier being 14 ft. in diameter.
"Outlines of Greek and Roman Medicine" by James Sands Elliott
Draw the cloaca (a) of a male, (b) a female dog-fish.
"Text Book of Biology, Part 1: Vertebrata" by H. G. Wells
Figure 7G, the last of this series, represents a section through the cloaca, caudad to the urinary openings, in the plane 1060 of figure 7.
"Development of the Digestive Canal of the American Alligator" by Albert M. Reese
The most important, which drained the forum, is known as the Cloaca Maxima and dates from the 6th century B.C.
"Encyclopaedia Britannica, 11th Edition, Volume 6, Slice 5" by Various

In news:

A journey through the American cloaca.