"Fat Cappin" is another expression for lying. "Fat Cappin" is a popular slang word originating from York, Pennsylvania.
Jabari: Yo bro I got some bomb head from a 10 last night ya dig?
Dequavis: Nah quit playing bro you
Fat Cappin.
Dequavis: Nah quit playing bro you
Fat Cappin.
by Official Webster Dictionary  July 16, 2019
 Get the Fat Cappinmug.
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