BROACH n. 2 definitions
A tool of steel, generally tapering, and of a polygonal form, with from four to eight cutting edges, for smoothing or enlarging holes in metal; sometimes made smooth or without edges, as for burnishing pivot holes in watches; a reamer. The broach for gun barrels is commonly square and without taper.…
BURR n.
The thin edge or ridge left by a tool in cutting or shaping metal, as in turning, engraving, pressing, etc.; also, the rough neck left on a bullet in casting. The graver, in plowing furrows in the surface of the copper, raises corresponding ridges or burrs. Tomlinson.