(tri·pan′) noun
1. An early form of the trephine.
2. A large rock–boring tool.
—v.t. ·panned, ·pan·ning
1. Mech. To use a trepan upon.
2. Surg. To subject to the operation of trephining.
3. To cut a hole partly through, as the back of a brush, for the insertion of bristles. Also trep·a·nize (trep′·ə·nīz). [<OF, a borer <Med. L trepanum a crown saw <Gk. trypanon a borer <trypaein bore]
—trep·a·na·tion (trep′ə·nā′shən) noun
—tre·pan′ner noun

(tri·pan′) Obs. & Archaic v.t.
To ensnare.
—noun A snare; trick; also, a trickster. Also spelled trapan. [<thieves' cant trapan <TRAP; prob. infl. in form by trepan¹]