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.
