The act of "helping" your bro in a sandbox game, by tagging along unwanted and generally annoying the other person by nudging them, standing in their way, walking in front of them, and taking all the resources that your bro would have found had you not been there.

Most often tied to games like Minecraft, Terraria, or any other open world, resource driven game.
"Look I found a whole bunch of diamonds!"

"Dude, fuck off, you're totally bro griefing me"

"What?"
by caidicus September 26, 2011
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