placentayoudaoicibaDictYouDict[placenta 词源字典]
placenta: [17] Latin placenta originally meant ‘flat cake’. It was borrowed from Greek plakóenta, the accusative form of plakóeis ‘flat cake’, which was derived from pláx ‘flat surface’ (possible relative of English plank). Its application to the afterbirth (originally in the phrase placenta uterīna ‘uterine cake’) is a postclassical development, inspired by the flat round shape of the afterbirth.
[placenta etymology, placenta origin, 英语词源]
placenta (n.)youdaoicibaDictYouDict
1670s of plants, 1690s of mammals, from Modern Latin placenta uterina "uterine cake" (so called 16c. by Italian anatomist Realdo Colombo), from Latin placenta "a cake, flat cake," from Greek plakoenta, accusative of plakoeis "flat," related to plax (genitive plakos) "level surface, anything flat," from PIE *plak- (1) "to be flat" (cognates: Greek plakoeis "flat," Lettish plakt "to become flat," Old Norse flaga "layer of earth," Norwegian flag "open sea," Old English floh "piece of stone, fragment," Old High German fluoh "cliff"), extended form of root *pele- (2) "flat, to spread" (see plane (n.1)). So called from the shape.