They are both; however, it does depend on the individual's perception of the event/activity. event - Is the word i would use in this situation... ("big dancing and singing show") 1 "something that happens or is regarded as happening; an occurrence, especially one of some importance." 2 "something that occurs in a certain place during a particular interval of time." Activity - Is not the word I would use unless its an 'event' where activities will be preformed (people doing things, often together, like building/creating, have contests, or playing games), it is a bit more specific in its meaning. 1"a specific deed, action, function" 2 "animation; liveliness" best, Nick