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O.S.1

or o.s.

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  1. (in prescriptions) the left eye.

Origin of O.S.1

From the Latin word oculus sinister

O.S.2

  1. Old Saxon.
  2. Old School.
  3. Old series.
  4. (of the calendar) Old Style.
  5. Also o.s. ordinary seaman.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for o.s.

o.s.

OS or O/S

abbreviation for
  1. out of stock
  2. banking outstanding
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