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1 definition by RockyRocky

 
1.
"Must Not"

Abbreviation often confused with the correct term: "Mustn't"

Confusion arises because of the pronounciation and feeling the "t" should be left out.
Colin musn't have been taught English in primary school.

OR

Nelson musn't lock himself outside of his house.
by RockyRocky August 30, 2007