What is Stir Shit?
1.
The act of saying things about other people that could have heavy implications if they were true, but which however you can't prove
Boris to Francesca: Hey fran you spent a very long time in the meeting with jeremy today. What were you doing in the room
Francesca to Boris: Shut up Boris don't stir shit, you know i have a bf
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2.
To stir shit means to address some issue which will metaphorically smell less if you leave it alone. (There has to be an issue there to begin with.)
You had to mention that, didn't you. You just had to stir shit!
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