Other forms: creepily; creepiest; creepier
Something is creepy if it feels like tiny things are crawling on you. The sensation of a spider on your arm is creepy.
Ladybugs are pretty, but it still feels creepy when they crawl across your hand. Another kind of creepy feeling is something that gives you an unpleasant chill, like a creepy ghost story or the creepy sound of footsteps in your attic at night. The earliest meaning of creepy was simply "characterized by creeping," so in the 18th century you'd be creepy if you were simply tip-toeing quietly through your house.