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definitions

arc tan

  1. arc tangent.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for arctan

arctan

abbreviation for
  1. arctangent: the function the value of which for a given argument is the angle in radians (between –π/2 and π/2) the tangent of which is that argument: the inverse of the tangent function
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