The definition of a ruckus is commotion or a noisy disturbance.(noun)
People yelling and getting into a fight in the middle of a movie is an example of a ruckus.
See ruckus in Webster's New World College Dictionary
Origin: prob. a merging of ruction & rumpus
See ruckus in American Heritage Dictionary 4
Origin: Perhaps blend of ruction
Origin: and rumpus.
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