to shape (a diamond) by rubbing with another diamond or a diamond chip.
Origin: back formation from bruting a rough hewing (of a diamond), partial translation of French brutage literally, a roughing, equivalent to brut rough, raw (see brute1) + -age-age
early 15c., "of or belonging to animals," from M.Fr. brut "coarse, brutal, raw, crude," from L. brutus "heavy, dull, stupid," an Oscan word, from PIE base *gwer- "heavy" (see grave (adj.)). Before reaching English the meaning expanded to "of the lower animals." Used of human