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C.T.A.F. stands for Can't Trust a Fart.
When you are just getting over a case of diarrhea and you don't know if your going to fart or shit your pants.
Honey wake up!! We need to change the sheets I just shit the bed. I have had the runs all day and thought it was safe but C.T.A.F.
by Mitchell Man July 10, 2008
Clearly they are fucking.
Fangirl 1: Did you see the picture of Jesse and Andrew?!
Fangirl 2: Mmmhm. CTAF.
by jessesgotaladyboner May 06, 2011