Definitions of riot:

noun: a public act of violence by an unruly mob
noun: a state of disorder involving group violence
noun: a wild gathering involving excessive drinking and promiscuity
noun: a joke that seems extremely funny
verb: take part in a riot; disturb the public peace by engaging in a riot
Example: "Students were rioting everywhere in 1968"
verb: engage in boisterous, drunken merry-making