This is the German word for "potato head". A rather silly and only slightly denigrating insult, it is mainly used to confuse people.
person 1: Haha I am smarter than you! Did you think that I would fall for the can of nuts trick? Kartoffelkopf!

prankster: huh?

person 1: That's right! I also know German!
by Marty Larel February 25, 2006
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