Meaning of pin-up in English\n\n a picture of a sexually attractive and usually famous person, especially someone wearing few clothes: Every wall in her bedroom was covered with pin-ups of her favorite pop star. informal. a person who is seen in pin-ups: With his perfect college-boy looks, he's the latest teenage pin-up.
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. Moreover, beginning in the 1940s, pictures of pin-up girls were also known as cheesecake in the U.S.