A body double is a general term for someone who substitutes for the credited actor of a character in any recorded visual medium, whether videotape or film.
The term is most commonly used in the context of head-to-toe (or nearly) shots involving nudity. For example, Catherine Bell served as a nude body double for Isabella Rossellini in the movie Death Becomes Her.
More specific terms are often used in special cases; a stunt double is used for dangerous or sophisticated sequences.
Stunt double and body double can both be used for cases where special skills are needed—anything from playing the piano, to competitive skiing.
Also, if only a part of the body is shown, the term might be more specific; probably the most common is a butt double, mostly used with TV, since whole-body nudity isn't as common in that medium.
The 1984 film Body Double, directed by Brian De Palma, featured a plot that hinged on the discovery that one character had in fact served as a body double for another; whether the nude scenes in question were actually done by either of the two actresses or by an uncredited body double is unclear.
See also: look-alike.
