pro·​trac·​tor | \prō-ˈtrak-tər, prə-\

Definition of protractor 

1a : one that protracts

b : a muscle that extends a part

2 : an instrument for laying down and measuring angles in drawing and plotting

Examples of protractor in a Sentence

Recent Examples on the Web

Sure, a protractor works, but a sextant does this even better. Rhett Allain, WIRED, "Figure Out Where You Are With Nothing But a Watch and Protractor," 3 May 2018 USA TODAY Sports The compass controversy is over, and the U.S. Golf Association has ruled that Bryson DeChambeau may no longer use his protractor on the course. Kevin Casey, USA TODAY, "USGA rules that Bryson DeChambeau can't use drawing compass on golf course," 6 July 2018 Now hold the protractor upside down and aim the straight part towards the North Star. Rhett Allain, WIRED, "Figure Out Where You Are With Nothing But a Watch and Protractor," 3 May 2018 Better whip out your protractor for this one, Meg … • Stop eating when the queen stops eating. Lisa Ryan, The Cut, "What Are the Most Bizarre Royal Etiquette Rules?," 3 May 2018 Last November, the can reappeared, only this time in sterling with a vermeil interior, as part of Krakoff’s Everyday Objects collection, which also includes a $9,000 silver ball of yarn and a $425 silver-and-walnut protractor. Christina Binkley, WSJ, "The Secret Inside Tiffany’s Blue Box: Reed Krakoff," 26 Mar. 2018 The pieces will include sterling silver protractors, rulers, a drinking straw, a first aid kit, and a paper cup. Stellene Volandes, Town & Country, "Inside the Secret World of Tiffany & Co.'s Silversmiths​," 12 Sep. 2017 Items needed for the Stuff the Bus campaign include: • Pencils (regular and colored), pens, markers (washable and dry erase) • Crayons, highlighters • Blunt edge scissors, protractors, compasses, erasers • Glue sticks and white glue bottles • The Aegis, "Harford Education Foundation's Stuff the Bus under way," 22 Aug. 2017 Key school supplies such as backpacks are tax-free, as are binders, calculators, compasses, composition books, pens, pencils, protractors, legal pads and more. Anna M. Tinsley, star-telegram, "Planning on tax-free shopping this weekend? Here’s how to survive and thrive," 9 Aug. 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'protractor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of protractor

circa 1611, in the meaning defined at sense 1a

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Statistics for protractor

Last Updated

26 Nov 2018

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Time Traveler for protractor

The first known use of protractor was circa 1611

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More Definitions for protractor



English Language Learners Definition of protractor

: a device that has the form of a half circle and that is used for drawing and measuring angles


pro·​trac·​tor | \prō-ˈtrak-tər \

Kids Definition of protractor

: an instrument used for drawing and measuring angles


pro·​trac·​tor | \-tər \

Medical Definition of protractor 

: a muscle that extends a part — compare retractor sense b

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More from Merriam-Webster on protractor

Rhyming Dictionary: Words that rhyme with protractor

Spanish Central: Translation of protractor

Nglish: Translation of protractor for Spanish Speakers Encyclopedia article about protractor

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