ri·ot·ous \ˈrīəd.əs, -ətəs\adjective Etymology: Middle English, from riote, riot debauchery, riot + -ous — more at riot 1. a.: practicing or marked by license or excess : profligate, wanton b.: abundant, exuberant, profuse < a riotous display of color > < riotous slapstick > 2.: of the nature of a riot : marked by public uproar and disturbance : participating in riot : turbulent, seditious