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radian

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noun ra·di·an \ˈrā-dē-ən\

Definition of radian

  1. :  a unit of plane angular measurement that is equal to the angle at the center of a circle subtended by an arc whose length equals the radius or approximately 57.3 degrees



1879

First Known Use of radian

1879


Medical Dictionary

radian

play
noun ra·di·an \ˈrād-ē-ən\

Medical Definition of radian

  1. :  a unit of plane angular measurement that is equal to the angle at the center of a circle subtended by an arc equal in length to the radius




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