I. noun
( -s )
: occurrence
happenings of major significance
II. noun
1. : an event or series of events designed to evoke a spontaneous audience reaction to sensory, emotional, or spiritual stimuli
2. : something (as an event) that is particularly interesting, entertaining, or important
the hearing is a happening , one of those unique events … which will be talked about for years — Douglas Kiker
III. adjective
Etymology: from present participle of happen (I)
1. : very fashionable : in herein
a happening hairstyle
2. : offering much stimulating activity
a happening dance club