Twitchy describes someone who is nervous, jumpy, or unable to stay still. A twitchy person might startle easily at sudden noises, fidget constantly, or seem on edge, like they're waiting for something bad to happen. You might feel twitchy before giving a big presentation or performing in a school play, when your legs bounce under your desk and your fingers drum on the table without you meaning to.

The word comes from twitch, which means a quick, jerky movement. When you're twitchy, your body makes these small, involuntary movements because you're anxious or overstimulated. A squirrel scanning for predators while eating an acorn looks twitchy, darting its head around at every sound.

People also use twitchy to describe things that move in quick, irregular ways. A twitchy cursor on a computer screen jumps around unpredictably. In video games, “twitchy” describes fast-paced gameplay requiring quick reflexes, like dodging obstacles or aiming rapidly.