To interrupt means to break into someone's speech or activity before they've finished. When you interrupt someone who's talking, you start speaking while they're still in the middle of their sentence. When a fire drill interrupts your math class, it stops the lesson before you've completed it.

Interrupting usually means cutting something off unexpectedly or inappropriately. If your little brother bursts into your room while you're reading and starts asking questions, he's interrupting your concentration. If a teacher interrupts a student's presentation to make an announcement, she's breaking into something already in progress.

The word carries different weight depending on context. Sometimes interruptions are necessary: a parent might interrupt two arguing children to restore peace, or a friend might interrupt you before you accidentally reveal a secret. But interrupting someone just because you're impatient or think your thoughts are more important is generally considered rude. It signals that you value your own voice more than listening to others.

People also use interrupt for things that break a pattern or flow: a storm might interrupt your baseball game, or a power outage might interrupt your favorite TV show. An interruption is the thing doing the interrupting, whether it's a person, event, or disturbance.