From fest, from German Fest (“festival”), abstracted from Volksfest, etc.
- A festival, a fest; used in names of events.
- summer → Summerfest
- Yule → Yulefest
- (informal) Appended to a noun to denote a thing, especially an event or artistic work, characterized by the noun's referent.
- snooze → snoozefest
- slug → slugfest
- action → actionfest
- joke → jokefest