pushpin
A small pin with a big head for pinning papers.
A pushpin is a short pin with a large, round, colored head used to attach papers to bulletin boards or walls. The head is usually made of plastic or metal and comes in bright colors like red, blue, or yellow, making it easy to grip between your thumb and finger. You press the sharp point into a corkboard or soft wall to hold up notices, photos, maps, or artwork.
Pushpins are everywhere: on classroom bulletin boards displaying student work, on bedroom walls holding up posters, or on office boards tracking projects. They're designed so you can push them in and pull them out easily without tools, unlike thumbtacks, which have flat metal heads that are harder to grip.
The word can also describe something small or trivial. People might call an issue a pushpin problem if it seems minor compared to bigger concerns, though what seems like a pushpin to one person might matter greatly to another.