A negative insult that is a combination of the portuguese word for fart ( buffa ) and the word biscuit. So basically, it means fart- biscuit. Can be used in place of the word idiot. Derived from Eoin Colfer's ... And Another Thing, which is the controversial 6th novel in the Hitchhikers Guide to the Galaxy series.
Dave: I don't get why people are always complaining about gas prices. I mean really, It's only like $2.00.
Marielle: Dave, that's the price per gallon. This car needs 20.
Dave: ohhh! I finally get it now!
Marielle: buffa biscuit.