meathead

noun3

1. •
   (slang) An ungainly, dull, or stupid person; someone who is lazy, disrespectful, and/or whose beliefs and philosophies clash with those of another.
2. •
   (slang) A large, muscular, stupid man, especially an athlete.

   • Gary was a hulking meathead who, when he wasn't playing football, was either hunting, fishing or getting drunk and rowdy in some topless bar.
3. •
   (Canada, slang) A member of the Canadian Forces Military Police.