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versed sine

noun Trigonometry.
  1. one minus the cosine of a given angle or arc. Abbreviation: vers.

Origin of versed sine

First recorded in 1590–1600
Also called versine, versin.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for versed sine

versed sine

noun
  1. a trigonometric function equal to one minus the cosine of the specified angleAbbreviation: vers

Word Origin for versed sine

C16: from New Latin sinus versus, from sine 1 + versus turned, from vertere to turn
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