Melancholia (from Greek: µέλαινα χολή, melaina chole), also lugubriousness, from the Latin lugere, to mourn; moroseness, from the Latin morosus, self-willed, fastidious habit; wistfulness, from old English wist: intent, or saturnine, was a concept in ancient and pre-modern medicine. Melancholy was one of the four temperaments matching the four humours. In the 19th century, "melancholia" could be physical as well as mental, and melancholic conditions were classified as such by their common cause rather than by their properties.
The name "melancholia" comes from the old medical belief of the four humours: disease or ailment being caused by an imbalance in one or other of the four basic bodily liquids, or humours. Personality types were similarly determined by the dominant humor in a particular person. According to Hippocrates and subsequent tradition, melancholia was caused by an excess of black bile, hence the name, which means "black bile", from Ancient Greek μέλας (melas), "dark, black", and χολή (kholé), "bile"; a person whose constitution tended to have a preponderance of black bile had a melancholic disposition. In the complex elaboration of humorist theory, it was associated with the earth from the Four Elements, the season of autumn, the spleen as the originating organ and cold and dry as related qualities. In astrology it showed the influence of Saturn, hence the related adjective saturnine.
Melancholia was described as a distinct disease with particular mental and physical symptoms in the 5th and 4th centuries BC. Hippocrates, in his Aphorisms, characterized all "fears and despondencies, if they last a long time" as being symptomatic of melancholia. When a patient could not be cured of the disease it was thought that the melancholia was a result of demonic possession.