Top definition
Tommy couldn't hear the shit that Warren was signing about him.
by will bitten December 21, 2016
Get the mug
Get a Si mug for your fish Paul.
2
Abbr. for 'stupid idiot'
As in Football Factory from 2004:
"Jog on, you si!"
by Nige Menzel May 24, 2007
Get the mug
Get a SI mug for your friend Trump.
buy the domain for your cat blog
3
S.I.S is an acronym for Special Investigation Section.

It is an Los Angeles Police Department's elite tactical detective squad with a straightforward mandate: Track down the City’s most dangerous offenders and take them off the street. S.I.S. are possibly the hardest-working, most dedicated men and women Detectives to wear a badge.
Alonzo: Hey, Mark, where are you transferring to?
Mark: S.I.S.
Alonzo: Yeah, S.I.S. Detective.
(from 'Training Day')
by KainJynez June 22, 2009
Get the mug
Get a S.I.S mug for your Facebook friend Rihanna.
4
Abbr. for "self-injury," also known as self-mutilation. Most common form is cutting, but may also include burning, bruising, skin-picking (excoriation), and other behaviors. There is no single cause for SI. SI is most common in women and tends to persist for years.
As a result of overwhelming anxiety, she turned to SI as a coping mechanism.
by rieux November 27, 2003
Get the mug
Get a SI mug for your buddy Vivek.
5
Means to "sit in silence" insetad of lol. Usually used if somebody sais something retarded online, its a good way to be honest. Lets face it very few actually laugh at stuff online.
xXihateyouxX: i was like "duhhhhhhh" haha
ay u guys 2003: s.i.s
by mat a April 24, 2005
Get the mug
Get a s.i.s mug for your cousin Bob.
6
stands for self-injury. Aka cutting, burning, etc. for emotional distress reasons
Person 1- Did you SI today?

Person 2- I haven't hurt myself on purpose in like a week.
by Injuried November 07, 2010
Get the mug
Get a SI mug for your sister Julia.
7
An awesome boy that is kind, nice, derpy, hilarious and clumsy and is a wonderful bestfriend.
Is that Si?!
by kjj-123 December 30, 2012
Get the mug
Get a Si mug for your father Vivek.