black humour
/ˌblak ˈhjuːmə/(US black humor)
noun
1 Medicine. The humour black bile; an unnatural, disease-causing humour derived from or resembling this; now historical and rare. Later also (in extended use): a depressed, angry, or sullen mood.
2Comedy, satire, etc., that presents tragic, distressing, or morbid situations in humorous terms; humour that is ironic, cynical, or dry; gallows humour.
Origin
Late Middle English; earliest use found in John Trevisa (c1342–?1402), translator. From black + humour. Compare atrabile, black bile, and the Latin and Greek parallels cited at those entries. Compare Italian (now hist.) umore nero black bile.