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straight angle

noun
  1. the angle formed by two radii of a circle that are drawn to the extremities of an arc equal to one half of the circle; an angle of 180°.

Origin of straight angle

First recorded in 1595–1605
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for straight angle

straight angle

noun
  1. an angle of 180°
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
straight angle in Science

straight angle

[strāt]
  1. An angle having a measure of 180°.
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