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definitions

shouldn't

[shoo d-nt]
  1. contraction of should not.

Usage note

See contraction, ought1.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for shouldn't

shouldn't

contraction of
  1. should not
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