SI

self injury.

cutting, carving, bruising, welting, etc.

you: damn... i hate emos.
me: ......
you: you SI?!?
me: ......

by 341103001 August 29, 2007

SiS

Shit is Situational.
(forum speak)

Person A: (When z1,) X > Y.
Person B: But when z2, Y > X!
Person C: *facepalm*C'mon guys, SiS.

by ShamayaXI September 12, 2009

SIS

An online term that depects ''Smile-In-Sight'' used when you don't go as far as to laugh, but a smile still spreads upon your face.

Janet: ''Stacy totally spilled Kool-Aid all over her dress!''

Wayne: ''SIS. That makes me smile''

by Kevin H***ley September 27, 2008

SIS

Secret Internet Shorty, an acronym used to describe pictures of a guys dick but using angles or photoshop to make appear significantly bigger than it really is.

Look at this dickture I just got from this guy! I know know for a fact he is a SIS!

by IamIwhoIam August 20, 2011

SI

Sports Illustrated

I done read SI.

by Andy L August 3, 2003

Si

An unbelievably rich cunt (richer than Bill Gates) who wears a monacle and probably has other characteristics but none you really care about.

Also likes boys and sniffing the sweatline under fat guys flabbing man breasts.

Brian has loads of money for beer tonight. He could do a Si and buy the pub free drininks all night.

by Bobby Charlton March 18, 2004

SIS

Due to the vast majority of lies which happens every time a person types 'LOL' in texting or the internet, SIS (Smile in Silence) is a much more proper use in times when one does not actually laugh when typing 'LOL'. Though, this may suggest that the person is not as fun as he did not actually laugh.

A: Yo, B, I just tried walking thru at a drive thru.
B: LOL, what happened?
A: B, stop lying bro, don't tell me you actually laughed at that message. SIS
B: Jeez, such a stickler...So what happened?
A: They told me that they only viewed car owners as acceptable customers.
B: SIS

by Shinigami Prophet July 10, 2014