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2.
Must not. Emphatically no. Have to not do it. Assuredly huh uh.
When it was a moment of choice she knew she musnt choose wrongly.
by dointhedeal50 January 26, 2009
 
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