Other forms: twitchier; twitchiest
Someone who's twitchy is either making quick, unintentionally jerky movements, or is visibly anxious. If you're waiting to hear if you got a part you desperately want in the school play, you may be understandably twitchy.
When someone twitches, their muscles are repeatedly contracting and releasing, they are twitchy. Your body may get a little twitchy after vigorous exercise, or your eye might tend to be twitchy when you're tired. People who are agitated or jumpy are also twitchy: "This movie's too suspenseful for me — it's making me twitchy!" Twitchy is from the 12th century to-twic-chen, "to pull apart with a quick jerk," and its Old English root which means "to pluck."