protractor
    n 1: drafting instrument used to draw or measure angles

Protractor \Pro*tract"or\, n.
   1. One who, or that which, protracts, or causes protraction.
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   2. A mathematical instrument for laying down and measuring
      angles on paper, used in drawing or in plotting. It is of
      various forms, semicircular, rectangular, or circular.
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   3. (Surg.) An instrument formerly used in extracting foreign
      or offensive matter from a wound.
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   4. (Anat.) A muscle which extends an organ or part; --
      opposed to retractor.
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   5. An adjustable pattern used by tailors. --Knight.
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