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.
To ensnare; to seduce, to trick.
1798 Charlotte Turner Smith: The Young Philosopher. Vol.4, Chapter 9. ...a postchaise, into which he had so infamously trepanned me...
The act of one who trepans.