[1] : The Collaborative International Dictionary of English v.0.48

calipers \cal"ipers\, n. pl. corrupted from caliber.
   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.
   1913 webster

   caliper square, a draughtsman's or mechanic's square,
      having a graduated bar and adjustable jaw or jaws.
      --knight.

   vernier calipers. see vernier.
      1913 webster
see also:
caliper compasses caliber compasses caliper square vernier calipers vernier 

[2] : WordNet (r) 2.0

calipers
     n : an instrument for measuring the distance between two points
         syn: caliper, calliper, callipers
see also:
caliper calliper callipers 

Calipers >> C Words
Calipers, definition of term: Calipers
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