radian
the measure of a central angle subtending an arc equal in length to the radius: equal to 57.2958°. Abbreviation: rad
Origin of radian
1Words Nearby radian
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024
How to use radian in a sentence
Strob, strob, n. the angular velocity of one radian per second.
The torsion couple per radian was determined by preliminary experiments.
British Dictionary definitions for radian
/ (ˈreɪdɪən) /
an SI unit of plane angle; the angle between two radii of a circle that cut off on the circumference an arc equal in length to the radius. 1 radian is equivalent to 57.296 degrees and π/2 radians equals a right angle: Symbol: rad
Origin of radian
1Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Scientific definitions for radian
[ rā′dē-ən ]
A supplementary unit of the International System used in angular measure. One radian is equal to the angle subtended at the center of a circle by an arc equal in length to the radius of the circle, approximately 57°17′44.6″.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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