melancholy

The word 'melancholy' originates from the ancient medical theory of the four humors, which held that human health and temperament were governed by four bodily fluids. It is a direct borrowing from Medieval Latin melancholia, itself from Greek melankholia, literally meaning "black bile" (melas "black" + kholē "bile"). An excess of black bile was believed to cause a persistent state of despondency and sadness. Over centuries, the term shed its purely physiological context and evolved into its modern abstract meaning, denoting a pensive, profound, and often lingering sadness.

Structure: melan (black) + choly (bile) 'melan' is from Greek melas (genitive melanos), meaning "black, dark." 'choly' is an Anglicized form from Greek kholē, meaning "bile."