late 14c., "containing black bile," a physiological sense now obsolete, from melancholy + -ic, or else from from Late Latin melancholicus, from Greek melankholikos "choleric," from melankholia "sadness," literally "(excess of) black bile" (see melancholy). Of persons or temperaments, "affected with melancholia, habitually gloomy," by 1789. The earlier adjective formation in Middle English was melancholian (mid-14c.), and melancholiac (mid-19c.) also was tried.
