The guy that purposely stands in the way in a bar or club waiting for someone to make eye contact or brush past him so he can start a fight.

A meathead will spend all his time lifting weights and generally being an arrogant prick whose goal primitively is based on intimidating other males who're often a lot smaller than them.

The mentality of a meathead is that having the capability to beat up the majority of normal sized males makes him better than everyone else and makes up for his poor intelligence.

A meathead will often make cruel/physical jokes to friends and acquaintances, meant to appear light hearted, but actually are just assertions of their power- which they'll follow by "i'm just pulling your leg" or "I was joking mate! Don't look so serious!".

Avoid these guys when they're out on the piss because they take the opportunity and pleasure to fight ANYONE. Can be identified by bulging muscles, tight tops and many girls under the age of twenty asking to buy them drinks.
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Someone using anabolic steroids doesn't necessarily make them a meathead, it's about mentality and ego-centricism rather than size and strength.
Friend 1: "Looks like another meathead is kicking off and spoiling everyones night again."

Friend 2: "Hopefully he's barred and we don't have to look a this dick week in week out."
by Max0491 February 14, 2011
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Typically a rather muscular person who walks around with their arms out to their side. Have no fear and love to start fights for no reason. Anthony or "Tony" is a typical meathead name. Shaved head and tattoos are characteristics of a meathead. Also known as a hardass. They carry around gallons of water acting to be some sort of muscle machine.
Meathead:"yo john, give me 20 bucks and ill knock this bitch ass out"
by Smurdax990 May 3, 2006
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Someone above average head, below average intelligence, spends a lot of their time looking in the mirror at their muscles,spends their free in the weight room, and grunts during reps.
Michael Parker was looking at his reflection while currling, when someone yelled hey meathead stop looking at yourself.
by n49333 October 2, 2008
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A meathead can be anyone of combo of the following things:

1. Someone who is muscular and slower in the brain.
2. Someone who marinates their head in sauce.
3. Someone who likes to put their heads in a grill of some kind (Ex. Barbeque, George Forman Grill, ect.)
4. Someone who is a complete fucking idiot.
A: Yo look at that guy, he's jacked!
B: Ya, but he's a fucking meathead though.

A: Why is that idiot grilling his own head?
B: Probably cause he's a fucking meathead.
by Rim Job Rob May 25, 2009
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Someone who posts their name on Urban Dictionary followed by a bunch of untruthful egotistical comments. Usually done by cowardly teenage jocks with undersized genitalia.
I'm tired of all those idiotic teenage meathead's posting useless definitions on urban dictionary and wasting the time of it's editors.
by CurvedMirror October 24, 2008
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