Deface

Defacing something means to vandalize or destroy something in appearance. Defacing something could be anything from carving something into desks belonging to a school or spray painting the side of a building. If you change something's appearance that does not belong to you without permission, it is considered defacing. You can get into lots of trouble for defacing something. If you spray painted the side of the white house, you would get into lots and lots of trouble. And if you carved a smiley face into a school desk, you would get in trouble but just not as much trouble.