n. A person who appears in the background of a scene in a television show or movie.
1998
When you stick to a script, it's like you are just a warm prop.
1997
So, what does the future hold for Simon Westaway? Bill Hughes, who certainly regards Westaway as more than just a warm prop, can see him branching out into other areas of film making.
1995 (earliest)
Next come the aloof adolescents intent on hanging around the beach like warm props on Baywatch, who can barely manage to carry their own sunglasses.