gelotology
Gelotology (noun) means the study of laughter and humour and how they affect the body.
Etymology
It derives from Ancient Greek γέλωτος (gélōtos), the genitive of γέλως (gélōs, “laughter”), combined with English -logy (a suffix denoting the study of a particular subject). The word was coined by the anthropologist and linguist Edith Trager, with participation from the American psychiatrist William F. Fry, Jr. (1924–2014), in March 1964.