- spleen
- c.1300, from O.Fr. esplen, from L. splen, from Gk. splen, from PIE *splegh- (cf. Skt. plihan-, Avestan sperezan, Armenian p'aicaln, L. lien, O.C.S. slezena, Lith. bluznis, O.Prus. blusne, O.Ir. selg "spleen"). Regarded in medieval physiology as the seat of morose feelings and bad temper. Hence fig. sense of "violent ill-temper" (1594).