A twist drill.
Any other style of cutter, for example a spade drill, that is rotated and fed in a similar manner as a twist drill to of cut a hole in metal, wood or other materials.
A tool used to bore through rock when sinking shafts.
A surgical instrument used to remove a circular section of bone from the skull; a trephine.
To create a large hole by making a narrow groove outlining the shape of the hole and then removing the plug of material remaining by less expensive means.
To use a trepan; to trephine.