n, pl  -acae   1 a  :  the common chamber into which the intestinal, urinary, and generative canals discharge in birds, reptiles, amphibians, and many 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 clo*acal adj 
 
 
 
Similar sounding terms:  click  clock  coeliac   co·lic 
 
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