While playing Halo 3, you hammer on the "B" button to lay a melee smack down. At the exact same instant your opponent also hammers on the "B" button and you beat each other down. This is often followed by a "You asshole" as well as "instabeat"!
Joe - "Hey Bob did you see that we both beat each other down in Halo 3."

Bob - "Yeah that was massive INSTABEAT! you R-Tard. Did you see what I did to your sister as well?? INSTABEAT!"
by cole199, bribarian February 9, 2009
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While playing Halo 3, you hammer on the "B" button to lay a melee smack down. At the exact same instant your opponent also hammers on the "B" button and you beat each other down. This is often followed by a "You asshole" as well as "instabeat"!
Joe - "Hey Bob did you see that we both beat each other down in Halo 3."

Bob - "Yeah that was massive INSTABEAT! you R-Tard. Did you see what I did to your sister as well?? INSTABEAT!"
by killacole/bribarian October 13, 2008
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While playing Halo 3, you hammer on the "B" button to lay a melee smack down. At the exact same instant your opponent also hammers on the "B" button and you beat each other down. This is often followed by a "You asshole" as well as "instabeat"!
Joe - "Hey Bob did you see that we both beat each other down in Halo 3."

Bob - "Yeah that was massive INSTABEAT! you R-Tard. Did you see what I did to your sister as well?? INSTABEAT!"
by cole p February 5, 2009
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