It is a street slang. You stand up and shit her/his face means "shit up your face"
- you smell like a shit, did some1 shit up your face?
- yeah thats why i hate 69 position all the time!
by abuzettin imanikilli June 17, 2009
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To open one's mouth and have incoherent garmble escape will little or no understandable meaning.

Can be likened to when a person combines two words on accident becuase they are thinking one and trying to say the other.
In response to a sentence that makes no sense : "You just shit your face man. Clean that up and talk to me when you're not a retard."

If someone frequently shits their face, they can be called a face shitter.
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