A common phrase on 4chan.

When a poster makes a thread on one of 4chan's niche boards that doesn't follow the theme of the board, or makes an incredibly stupid and/or immature (and unfunny) comment (eg: being racist, saging for no good reason, using "your mom") they will be told

by the masses to Go Back To /b/ (or Gb2/b/)
Thread: "This chick (insert picture of black girl here) asks you out on a date, what do you do?"

Anonymous: "LOLNO NIGGERS GOT AIDS"

Other Anon: "Gb2 /b/"
by JFGDS May 31, 2009
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In reference to the internet image board 4Chan, refers to moving a discussion to a certain board on the site. In gb2/b, for instance, the user is telling another user to move a discussion to /b, one of the several boards on the site. This is used when the discussion is completely out of context to a select section's subject matter.
by Mel December 21, 2004
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