1595-1605; back formation from chamfering (taken as chamfer + -ing1) < Middle Frenchchamfrein, variant of chanfreint beveled edge, orig. past participle of chanfraindre to bevel, equivalent to chant edge (< Latincanthus; see cant2) + fraindre to break < Latinfrangere; see frangible
1601, "small groove cut in wood or stone," from M.Fr. chanfraindre (Mod.Fr. chanfreiner), pp. of chanfraint, second element from L. frangere "to break;" perhaps the whole word is cantum frangere "to break the edge." Meaning "bevelled surface of a square edge or corner" is attested from c.1840, of uncertain connection to the other sense.