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definitions

you'll

[yool; unstressed yoo l, yuh l]
  1. contraction of you will: You'll never guess who was here.
Can be confusedyou'll yule

Usage note

See contraction.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for you'll

you'll

contraction of
  1. you will or you shall
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