As a former Klansman, I can confirm that the definition of 311 below is indeed correct!

The eleventh letter of the alphabet is the letter "K"; thus 3 times 11 equals "KKK," or Ku Klux Klan. 311 is sometimes used as a greeting to demonstrate membership in the KKK or simply sympathy with the Klan and its ideology.

There is also a popular rock band with the name "311" which is not at all hate-oriented, completely different meaning.
This is not bullshit, 311 is also used by KKK members!

Great band too, not in any way affiliated with the Ku Klux Klan or any other racist groups.
by Jordan July 4, 2006
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an excitable alternative-reggae/metal band started n early 90's thats all about being yourself, positive vibes/ PEACE LOVE & UNITY. if u hate on this band, u have either zero taste in music/rythm, or you're just a miserable fuck. (uncontested live shows)---311 is the omaha PD code for indecent exposure
we only entered in one contest that we made up ourselves- to b the 311est
by Tx2Wa311 March 16, 2013
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Stands for Crip Killer.

3rd letter in alphabet= C

11th letter in alphabet= K

CK- Crip Killer
Throw up that 311 if you down wit Bloodz.
by 031 CKA June 29, 2006
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A really shitty bad that should have quit a long time ago.
My god this song sucks. Is this Limp Bizcut?
Oh no, its 311. My bad.
by Big Ern August 28, 2005
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Someone going to 3 eleven concert says i going to 311 concert.
You mean 3 eleven not 311.
by Kuehlstein February 12, 2018
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the band that sings "that one song"
Kyle: oh I know this song, who sings this song?
Greg: no clue
Joe the bitch: that's 311 guys
Kyle: Joe, you're such a bitch
Greg: yeah Joe shut up
by 311fanjoe March 11, 2019
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"yo man, i really 311 you."
by neefs March 11, 2009
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