A pin-up model is a model whose mass-produced pictures and photographs have wide appeal within the popular culture of a society. Pin-up models are usually glamour models, actresses, and fashion models whose pictures are intended for informal, aesthetic display, such as being pinned onto a wall.
Every wall in her bedroom was covered with pin-ups of her favorite pop star. a person who is seen in pin-ups: With his perfect college-boy looks, he's the latest teenage pin-up.