A bust is a sculpted or cast representation of the upper part of the human figure, depicting a person's head and neck, and a variable portion of the chest and shoulders. The piece is normally supported by a plinth. These forms recreate the likeness of an individual. These may be of any medium used for sculpture, such as marble, bronze, terracotta or wood. A parallel term, aust, is a representation of the upper part of an animal or mythical creature.

Sculptural portrait heads from classical antiquity are sometimes displayed as busts. However, these are often fragments from full-body statues, or were created to be inserted into an existing body.