WordWeb Online

1. A mutual promise of a couple not to date anyone else; on college campuses it was once signaled by the giving of a fraternity pin

1. To hold fast or prevent from moving
   "The child was pinned under the fallen tree";
   - trap, immobilize, immobilise [Brit]
    
2. Attach or fasten with pins
   "pin the needle to the shirt"
    
3. Pierce with a pin
   "pin down the butterfly"
    
4. (chess) immobilize a piece

Derived forms: pinnings

Type of: aggress, attack, empale, fasten, fix, impale, promise, secure, spike, transfix

Antonym: unpin

Encyclopedia: Pinning