An outburst is a sudden, forceful expression of emotion that bursts out of someone, like a balloon popping. When a toddler has an outburst in the grocery store, they might suddenly start crying and yelling because they can't have candy. When a student has an outburst of laughter during a serious assembly, they couldn't keep it inside any longer.

Outbursts usually happen when feelings become too strong to control: anger, frustration, joy, or grief. They're called outbursts because the emotion bursts out unexpectedly and intensely. A teacher might have an outburst of anger after students ignore warnings repeatedly. Your little sister might have an outburst of excitement when she sees birthday presents.

The word often suggests a loss of self-control, which is why people might apologize after an outburst: “Sorry for my outburst earlier.” While everyone has strong feelings, an outburst means those feelings burst out suddenly and visibly, often catching others by surprise.