An awl with a blade similar to a small, straight screwdriver; used for making holes, especially in wood to take screws.
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.