Is there a term to refer to the back view of a person?

In art, back view and rear view are both widely used for images of this sort.

Bridgeman art library uses "rear view" as a tag (search) while the National Portrait Gallery in London seems to prefer "back view" (search); the Smithsonian uses both but more "back view" (search).

(Sorry this isn't a single word answer, but it's not clear if one is required because the tag seems to contradict the question.)