"secreting organ of the body," O.E. lifer, from P.Gmc. *librn (cf. O.N. lifr, O.Fris. livere, M.Du. levere, O.H.G. lebara, Ger. Leber "liver"), perhaps lit. "fatten up." In M.E. it rivaled the heart as the supposed seat of love and passion, hence lily-livered.