CALIPER

I. noun Etymology: alteration of caliber Date: 1588 1. any of various measuring instruments having two usually adjustable arms, legs, or jaws used especially to measure diameter or thickness, a device for pressing a frictional material (as a brake pad) against the sides of a rotating wheel or disc, thickness especially of paper, cardboard, or a tree, II. transitive verb (-pered; ~ing) Date: 1876 to measure by or as if by ~s