The REAL Big four, unlike someones definition, are the kings of thrash metal.
The big four are:
Metallica
Megadeth
Anthrax
Slayer
In that order
by EIEKTRICEYE September 17, 2011
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Usually relates to the "Big Four" Grunge bands of the early '90s.
The Big Four are:

Soundgarden
Pearl Jam
Alice in Chains
Nirvana

Even more interesting, they all come from Seattle
"The Big Four were pioneers for the Grunge genre, not to mention, they just plain kick ass!"
by GrrTigerMonster April 8, 2009
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There are four essential items in any mans life: pound the pussy, eat some food, good shit, and a nice nap. Pound. Eat. Shit. Nap.

The big four is when you can hit all those items in a single day. But it only counts when you hit all four. You can't count two eats, one shit, and one nap, as a big four. However, once the four are completed in a single day, you can add on additional items for a Big Five, Big Six, and so on.
Hey Hal, did you get the big four this weekend? No, the old bag wouldn't let me pound!
by BigJohnson77 October 31, 2015
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The Four Largely Popular thrash metal bands that formed in the 1980's. These bands dominated the thrash scene.
They were,Metallica,Megadeth,Slayer and Anthrax.

runners up include-
Exodus,Death Angel,Overkill, destruction and Kreator
the big four of thrash were influenced by hardcore music and NWOBHM and went on to inspire nearly all of todays metal. Slayer Alone is said to be one of the forefathers of death metal.
by kane the main mclain July 11, 2008
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Big Four Of Melodeath :

In Flames = Metallica
At the Gates = Slayer
Dark Tranquillity = Megadeth
Soilwork = Anthrax

People only like In Flames' early albums
Lots of people like DT the most out of the 4
AtG have one really popular album that influenced a ****load of bands
And none really cares about Soilwork

Bob: In flames is awesome
Tim: Yeah so is the other Big Four Of Melodeath At the Gates, Dark Tranquility, and Soilwork
Bob and Tim: \m/
by knixx October 7, 2007
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the four biggest and best thrash metal bands. metallica, megadeth, anthrax and exodus
metallica, megadeth, anthrax and exodus are the big four of thrash
by jkgvfhgk December 22, 2006
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