What is your definition of a meathead?
Thanks for asking.
My definition is flexible, but there are usually 3 salient characteristics. Although political leanings are NOT one of them, the majority of meat heads seem to be righties. There are exceptions, sometimes.
1/ Wants very much to be seen as an alpha male (rarely, you might see a female alpha wannabe) but can't attain the status IRL so seeks to establish it online by acting the way he THINKS a a real alpha acts.
2/ Rarely if ever brings fresh content to any thread, seeks in most posts to (a) post hump, (b) seek attention for himself, (c) brag incessantly, (d) feign some sort of intellectual or material or physical superiority (abusing a panel counts too.) (e) Obsessive about trying to get in the Last Word. As a substitute for the lack of content, will post endlessly and repetitively about a handful of politically extreme talking points... all of which are either plagiarized or mind crushingly moronic... or both.
3./ The deeper a conversation gets into actual content, the sooner he will resort to deflections such as ad homs and "flaming" but since the IQ decreases rapidly with heat and frenzy, there is usually only one arrow in his quiver per poster and it's been shot so many times the fletches have mostly deteriorated and the head is blunted. Ultimately when all else fails, he will claim "victory" and bail... but of course due to the Last Word obsession he'll be back the next day ready to gaslight.
~~ (hat tip to Blurt [I think it was] for the quiver & arrow analogy.)