"431" is a term that refers to a bunch of redneck queers who shacked up together back in the late 1990's.

Today, "431" is commonly used to refer to "herpes spreaders" of the homosexual variety.

"Man, those herpes spreaders are definitely members of Team 431. What a bunch of friggin' 431s!"
by Sonic Boom May 12, 2006
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When your so god damn too fucking bored you end up breaking Urban dictionary and end up getting this on your screen.
Guy 1: I just got this message on my screen when typing qeqtyhreuyvyasujicdfvdsucaijxoscndbvhsnciamxc smcdkmvemkv cmsdfk vfb vbndfdnfbndfkmbkdmkdfgkmbgkdmfgkdmgkdmkgmfa,sfsf,sofodg,sof,sfoofofofd *whatever.* it says: Bad Message 431 reason: Request Header Fields Too Large
Guy 2: oh... you're so bored you broke it!
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