secreting organ of the body, Old English lifer, from Proto-Germanic *librn (source also of Old Norse lifr, Old Frisian livere, Middle Dutch levere, Dutch lever, Old High German lebara, German Leber "liver"), perhaps from PIE root *leip- "to stick, adhere," also used to form words for "fat."
Formerly believed to be the body's blood-producing organ; in medieval times it rivaled the heart as the supposed seat of love and passion. Hence lily-livered, a white (that is, bloodless) liver being supposed a sign of cowardice, Shakespeare's pigeon-livered, etc. Liver-spots, once thought to be caused by a dysfunction of the organ, is attested from 1730.
It forms all or part of: adipose; beleave; delay; leave (v.); lebensraum; life; liparo-; lipo- (1) "fat;" lipoma; liposuction; lively; live (v.); liver (n.1) "secreting organ of the body;" Olaf; relay.
It is the hypothetical source of/evidence for its existence is provided by: Greek liparein "to persist, persevere," aleiphein "anoint with oil," lipos "fat;" Old English lifer "liver," læfan "to allow to remain."
late 14c., epatike, from Old French hepatique or directly from Latin hepaticus "pertaining to the liver," from Greek hēpatikos, from hēpar (genitive hēpatos) "liver" (see hepatitis). As a noun, "medicine for the liver," from late 15c.
1727, from Greek hēpatos, genitive of hepar "liver," from PIE root *yekwr- (source also of Sanskrit yakrt, Avestan yakar, Persian jigar, Latin jecur, Old Lithuanian jeknos "liver") + -itis "inflammation."