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definitions

shan't

[shant, shahnt]
  1. contraction of shall not.

Usage note

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

shan't

contraction of
  1. shall 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
Word Origin and History for shan't

by 1660s, "colloquial" [OED] contraction of shall not.

Online Etymology Dictionary, © 2010 Douglas Harper