melonhead

Compound of melon +‎ head.

melonhead (plural melonheads)

1. (US) One of a group of legendary beings, known in parts of Michigan, Ohio, and Connecticut, and generally described as small humanoids with bulbous heads who occasionally emerge from hiding-places to attack people.
2. (Australia, US, informal, derogatory) A fool or idiot.

   Synonyms: see Thesaurus:fool

   • 1992, P. J. Peterson, Liars, New York, N.Y. […]: Scholastic Inc., published 1994, →ISBN, page 162:

     Uncle Gene turned toward Dad. "Let the melonhead laugh. We'll show him, won't we, pard?"

   • 1999, Kevin Sampson, Powder: An Everyday Story of Rock 'N' Roll Folk, London: Jonathan Cape, →ISBN, page 477:

     The picture showed the group, a gurning, multichinned James looking like a melonhead in the foreground, dressed in formal evening-wear and cummerbunds. How the fuck had they got hold of those pictures? The boys looked like a cabaret band. It was bad. It was very bad.

   • 2005 April 21, Lee Harris, “Shefield and the Fan”, in alt.sports.baseball.bos-redsox‎ (Usenet):

     Of course you should you melonhead. Why are you being so obtuse. You are just making my whole point.

• Jonathon Green (2024) “melonhead n.”, in Green’s Dictionary of Slang