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definitions

stage left

noun Theater.
  1. the part of the stage that is left of center as one faces the audience.

Origin of stage left

First recorded in 1930–35
Also called left stage.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for left stage

stage left

noun
  1. the part of the stage to the left of a performer facing the audience
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