si

Abbr. Simple Simon. Individual renowned for extreme stupidity and slowness of mind.

"Jog on you si - you're as thick as pigshit" or "he's a proper si that one, thicker than a King Edward yoghurt"

by Phileas May 20, 2008

SIS

acronym for snicker inside - use instead of LOL when describing what one is actually doing when one chats/texts.

person a: I blacked out last night and lost my pants.
person b: SIS. You friend, are unpredictable.

by omniv0re December 28, 2011

Sis

1. A term used as a confidence booster by black females in order to 'hype' their self-esteem.

2. A phrase used frequently by close female friends who share a special bond from others.

3. A term used by a female to reassure another female that she will always be there to defend, honour and keep her from committing bad decisions.

Kidist, you mah sis and always will be. Happy Birthday boo 💛

by kidoblack February 19, 2018

si

synthetic intelligence.

Artificial intelligence derived from synthetic materialism.

SI is the only path to achieve artificial intelligence.

by sandraxine June 20, 2018

Si! Si! Como!

Every GuitarHeroStyles reaction that has ever existed in the history of ever.

*Beats Tartarus*

Person 1: Si! Si! Como!? *breathes* COMO!? SI!!!!

by VoidCrypt October 15, 2020

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