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1.
To shit on one's face is to "mess", or kid with one's self. Similar to "Nah, I'm just shitting you".
Person a)"Dude, your Mum just died..."

Person b)"...Omg..."

Person a)"LOL! Nah I'm just shitting on your face!"

"<suprising comment>"

"Dude, dont shit on my face, are you serious?"
by K.1.3.R.4.N September 05, 2006
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