ˈkidnē, -ni noun
( -s )
Usage: often attributive
Etymology: Middle English kidenei, kidney, from kiden-, kidn- (origin unknown) + ei, ey egg, from Old English ǣg — more at egg
1.
a. : one of a pair of vertebrate organs situated in the body cavity near the spinal column that serve to excrete urea, uric acid, and other waste products of metabolism, that in man are bean-shaped organs about 4 1/2 inches long lying behind the peritoneum of the posterior part of the abdomen and embedded in a mass of fatty tissue, and that consist chiefly of nephrons by which urine is secreted, collected and finally discharged into the pelvis of the kidney whence it is conveyed by the ureter to the bladder to be periodically discharged — compare mesonephros , metanephros , phonephros
b. : any of various more or less complex excretory organs of invertebrate animals — see green gland ; compare nephridium
2. : sort or kind especially as regards persuasion, disposition, or temperament
a nice helpful guy, of a different kidney entirely from the ubiquitous Secret Police functionaries — Paula Lecler
3. : a kidney-shaped aggregate of ore
Synonyms: see type