shouldn'tve

A contraction of "should not have." It can be punctuated many different ways (ie. should'nt've, should'ntve, shouldn't've, etc)
You shouldn'tve called in sick yesterday, there were free donuts in the break room.
by hedfones February 18, 2009
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would'nt've

A contraction of would-not-have.
I would'nt've drank that milk had I known it was soy milk.
by hedfones March 08, 2008
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