A rumpus is a noisy disturbance or commotion, the kind of uproar that makes adults stop what they're doing and investigate. When a group of kids starts a pillow fight that gets out of hand, with feathers flying and furniture getting knocked over, that's a rumpus. When the whole cafeteria erupts in laughter after someone's tray goes crashing to the floor, you might say there's quite a rumpus going on.

The word captures both the noise and the chaos of the moment. A rumpus combines sound and activity into one unruly scene: it's loud like a fire alarm and messy like spilled paint, with people or animals creating the disorder. Picture a dozen puppies suddenly let loose in a quiet library, or imagine three siblings arguing loudly about whose turn it is while simultaneously chasing each other around the furniture.

Maurice Sendak's classic children's book Where the Wild Things Are features the famous line “Let the wild rumpus start!” as the creatures begin their rowdy celebration, showing exactly what the word means: joyful, wild, noisy fun that's completely out of control.