From WordNet (r) 3.0 (2006) [wn]:
nightlife
n 1: the entertainment available to people seeking nighttime
diversion [syn: nightlife, night life]
2: the activity of people seeking nighttime diversion (as at the
theater, a nightclub, etc.); "a futile search for intelligent
nightlife"; "in the summer the nightlife shifts to the dance
clubs" [syn: nightlife, night life]