bev·el / ˈbevəl/ • n. a slope from the horizontal or vertical in carpentry and stonework; a sloping surface or edge. ∎  (in full bev·el square) a tool for marking angles in carpentry and stonework.• v. (bev·eled, bev·el·ing or bev·elled, bev·el·ling) [tr.] [often as adj.] (beveled) reduce (a square edge on an object) to a sloping edge: a beveled mirror.ORIGIN: late 16th cent. (as an adjective in the sense ‘oblique’): from an Old French diminutive of baif ‘open-mouthed,’ from baer ‘to gape’.

bevel † adj.: (her.) having two equal acute alternate angles XVI; oblique XVII; sb.; joiner's tool for setting off angles; slope, sloping surface XVII. — OF. *bevel, F. bi-, béveau etc. (XVI), f. OF. baif open-mouthed, f. baer gape; cf. OF. bever give bias to.