From Longman Dictionary of Contemporary Englishfestfest /fest/ noun → a beer/song/food etc fest → slugfest
Examples from the Corpus
fest• Sedona ran its second annual film fest a few weeks ago.• There are a number of exciting acts featured at this year's fest.-fest-fest /fest/ suffix [in nouns] informalused to form nouns referring to events that have a lot of a particular thing or have a very great effect of a particular kind a talkfest a snoozefest (=a very boring event)Origin fest (1800-1900) German Latin festum; → FESTIVE 