In german Affenkopf (also: Affenkopp) is used to a person, who is stupid or does something stupid.
Depending on the context and intonation it can be more or less offensive.
Ah, ich bin so ein Affenkopf! (Ah, silly me!)
Du bist so ein elender Affenkopf! (You are so fucking retarded!)
by Affenkopp January 9, 2012
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