1. A surgical instrument used to remove sections of bone from the skull
   "The neurosurgeon used a trepan during the delicate brain surgery";
   - trephine
    
2. A drill for cutting circular holes around a centre
   "The jeweller used a trepan to carefully cut a hole in the delicate gemstone"

1. Cut a hole with a trepan, as in surgery
   "The surgeon trepanned the skull to relieve pressure"

Derived forms: trepanned, trepans, trepanning

Type of: bore, drill, surgical instrument

Encyclopedia: Trepan