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arc sine

noun Trigonometry.
  1. the angle, measured in radians, that has a sine equal to a given number. Abbreviation: arc sin, arcsin; Symbol: sin−1

Origin of arc sine

First recorded in 1905–10
Also called inverse sine.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for arcsin

arcsin

abbreviation for
  1. arcsine: the function the value of which for a given argument between –1 and 1 is the angle in radians (between –π/2 and π/2), the sine of which is that argument: the inverse of the sine 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
arcsin in Science

arc sine

  1. The inverse of the sine function.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.