SIS 

suck it slow

i want you to SIS

SIS by foonster March 8, 2010

sis 

stay in school, from peaches song "fuck the pain away"

sis iud stay in school cuz it's the best

sis by peter brook August 2, 2008

SIS 

Typical abbreviation for the Saying "Slaves in shackles", Racist.

"Don't do that sis" (Don't do that, slave in shackles" "are you a sis?" (Are you a slave in shackles?)

SIS by Educational Institutions January 6, 2022

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.

SIS 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 💛

Sis by kidoblack February 19, 2018

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.

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''

SIS by Kevin H***ley September 27, 2008