- (n.) 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.
- (n.) One who or that which, protracts or causes protraction.
- (n.) A muscle which extends an organ or part; -- opposed to retractor.
- (n.) An adjustable pattern used by tailors.
- (n.) An instrument formerly used in extracting foreign or offensive matter from a wound.
Webster's Revised Unabridged Dictionary
| APA | Webster's. (2011). protractor. Retrieved September 20, 2026, from http://smartdefine.org/protractor/definitions/2050288 |
| Chicago | Webster's. 2011. "protractor" http://smartdefine.org/protractor/definitions/2050288 (accessed September 20, 2026). |
| Harvard | Webster's 2011, protractor, Smart Define, viewed 20 September, 2026, <http://smartdefine.org/protractor/definitions/2050288>. |
| MLA | Webster's. "protractor" 27 May 2011. Web. 20 September 2026. <http://smartdefine.org/protractor/definitions/2050288> |