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1.
an acronym for the Syracuse University Marching Band, or the "Pride of the Orange"
Guy 1: Why do I even go to Syracuse football games?
Guy 2: To watch Otto and the SUMB, not for legit Div. 1 football...
by cusekid March 11, 2009
 
2.
SUMB is an abbreviation for Super Ultimate Mother Bitch. It refers to the leader of the bitchhood. Typically, the SUMB is beyond bitchy and is known for flirting with guys.
What!? Mandy is a SUMB? No wonder she is so ugly and mean yet always tries to flirt with guys. She is beyond cheap and disgusting.
by lengjai123 June 15, 2010
 
3.
an acronym for "Snickering Under My Breath" as a more realistic alternatitive for LOL "Laughing out loud"
A: I probably just failed my algebra final.
B: Yeah, sumb
by WatchIt2 February 03, 2010
 
4.
sumb=so dumb. invented by Ammie, so thanks for that
Chelsea is not very attractive and she's sumb.
by huxflux February 07, 2005
 
5.
It means Shut Up Motherfuckin' Bitch. That's all. Used for pesky nerds saying "You're ugly" and all sorts of criticism or whatever.
SUMB! You're just a nerd.
by doubtful pensive July 20, 2006