- happening (n.)
- mid-15c., "chance, luck," verbal noun from happen (v.); meaning "an occurrence" is 1550s. Sense of "spontaneous event or display" is from 1959 in the argot of artists. Happenings "events" was noted by Fowler as a vogue word from c. 1905.
- happening (adj.)
- 1520s, "occurring," present participle adjective from happen (v.).