1. A head that is oblong and bulbous at the top, especially when seen without hair. I've got a bit of a peanut head, so I hope I never go bald!
2. A socially inept or foolish person; a dweeb or dork. Yeah right, I would never go on a date with a peanut head like you!
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
n. an oaf; a nerd. You are so silly, Kim. You’re a real peanut head!
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved.