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Term used by 'Diary of a Wimpy Kid' as a 'your mom' joke.
Substitute Teacher: Greg, can you answer this problem?
Greg: Your Mama!
Substitute Teacher: Excuse Me?
Greg: Your Big Fanny Granny!
Substitute Teacher: Well I hardly think that's -
Greg: Your Slaphappy Grandpappy!
by middle_school_'lOsEr' December 30, 2009

Words related to Your Big Fanny Granny

your slaphappy grandpappy diary of a wimpy kid your mama your mom