Sis

A sexual nickname used by gang members

Hey sis

by Gang guy 254 October 14, 2016

SI

Level Trim for Honda Civic and etc... it means.. SLOW IMPORT..

That SI got beat by my geo.

by HawkINX4 April 14, 2004

Sis

A perfect response to your friend saying something stupid, bitchy, slutty or just something u can't think of a reply to

Person 1: Idk which guy to meet this weekend, there's a choice of 3
Person 2: sis

by Theteakeeper January 12, 2019

IUD SIS / SIS IUD

This is an acronym from the Peaches Song "Fuck the Pain Away." While "SIS" probably does stand for "Stay In School" "IUD" does NOT stand for "Injustice Under Dog" as stated in the other listing for this pair of acronyms. It stands for "Intra-Uterine Device," a free form of birth control provided by Planned Parenthood. Peaches is encouraging girls to stay in school by not getting pregnant.

"IUD SIS / SIS IUD... stay in school cause it's the best."

by morebettermostrighter January 9, 2010

SI

Organization of sensation for use.
A type of therapy effective for children with processing disorders including autism.

therapists facilitate a child's intrinsic understand of body sensations to better interact with the understanding of everything that is not the body

by occupational therapist December 14, 2004

si

Abriviation for suck it, normally used on MMORPG's to make fun of the loser.

Oh, man! Did you just see that head shot? Bet you didnt see that coming loser! SI n00b! Better luck next time!

by Nicholson L. May 17, 2006

Si

SI : meaning ha ha ha(in a sarcastic tone)or your not very smart
randomly made up on the spot because someone mispelt my name so i said si (because that was the bit they missed out) he said "what?" so i carried on saying si just to make him feel like he'd missed out on something. now it is a word! i hope:)

someone makes a joke about you thats not very funny you say "si si"
OR
someone answers a question wrong you say "si" and laugh

by Hannah macintosh April 11, 2004