From Middle English joli, jolif (“merry, cheerful”), from Old French joli, jolif It is uncertain whether the Old French word is from Old Norse jól (“a midwinter feast”)  (more at yule), in which case, equivalent to yule + -ive; or ultimately from Latin gaudere (more at joy). For the loss of final -f in English compare tardy, hasty, hussy, etc.
- Full of high and merry spirits; jovial.
jolly (plural jollies)
- JOLLY in the 1911 Encyclopedia Britannica, vol. 15, p. 495.
jolly m (invariable)