calipers

Cal"i*pers, n. pl. Etym: [Corrupted from caliber.] Defn: An instrument, usually resembling a pair of dividers or compasses with curved legs, for measuring the diameter or thickness of bodies, as of work shaped in a lathe or planer, timber, masts, shot, etc.; or the bore of firearms, tubes, etc.; -- called also caliper compasses, or caliber compasses. Caliper square, a draughtsman's or mechanic's square, having a graduated bar and adjustable jaw or jaws. Knight. -- Vernier calipers. See Vernier.

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