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Definition of "protractor" [pro•tract•or]

  • A semicircular instrument for measuring and constructing angles. (noun)
  • An adjustable pattern used by tailors. (noun)
  • Anatomy A muscle that extends a limb or other part. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Use "protractor" in a sentence
  • "That is, hold the protractor, which is "D" shaped, in the same orientation as the letter "D"."
  • "-- As all angles are not obtainable by the square or bevel, a protractor is a most desirable addition to the stock of tools."
  • "A 14-year-old Naples High School student faces felony charges of aggravated battery for allegedly attacking another teen at the Coastland Center mall with an instrument described as a protractor or compass."