a dramatic genre most closely associated with the English playwright Ben Jonson (Jonson, Ben) from the late 16th century. The term derives from the Latin humor (more properly umor), meaning “liquid,” and its use in the medieval and Renaissance medical theory that the human body held a balance of four liquids, or humours: blood, phlegm, yellow bile (choler), and black bile (melancholy). When properly balanced, these humours were thought to give the individual a healthy mind in a healthy body.

In his play Every Man Out of His Humour (1599), Jonson explains that the system of humours governing the body may by metaphor be applied to the general disposition, so that a peculiar quality may so possess a person as to make him or her act in one way. Jonson's characters usually represent one humour and, thus unbalanced, are basically caricatures. Jonson distinguished two kinds of humour: one was true humour, in which one peculiar quality actually possessed a man, body and soul; the other was an adopted humour, or mannerism, in which a man went out of his way to appear singular by affecting certain fashions of clothing, speech, and social habits.