To scare means to cause sudden fear or alarm in someone or something. When you jump out from behind a door and yell “Boo!” you scare your sister. A loud thunderclap can scare a dog, sending it running under the bed. Horror movies are designed to scare audiences with suspense and startling moments.

The feeling of being scared can range from a quick startle to genuine terror. You might get a little scare when your phone rings unexpectedly in a quiet room, but you'd be truly scared if you were lost in the woods at night. Something scary creates fear: a scary story, a scary mask, a scary situation.

A scare can also be a noun meaning a sudden frightening event or a widespread alarm. A health scare happens when people worry about a disease spreading. Your parents might say you gave them quite a scare when you came home late without calling. Sometimes threats turn out to be just a scare, meaning the danger wasn't as serious as people initially feared.

People use scare in phrases too. To scare up something means to gather it with effort, like scaring up enough players for a basketball game. A scarecrow is designed to frighten birds away from crops.