melancholy (n.) Look up melancholy at Dictionary.com
c.1300, "condition characterized by sullenness, gloom, irritability," from O.Fr. melancholie, from L.L. melancholia, from Gk. melankholia "sadness," lit. "black bile," from melas (gen. melanos) "black" (see melanin) + khole "bile" (see Chloe). Medieval physiology attributed depression to excess of "black bile," a secretion of the spleen and one of the body's four "humors." Adj. sense of "sullen, gloomy" is from 1526; sense of "deplorable" (of a fact or state of things) is from 1710.