Si

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

si

Its a model of faster model of the Honda Civic, meaning "Sport Injection"

My civic DX got spanked by that Si hatck.
or
Im bout to get me some Si rimz dawg.

by Tsugaru November 26, 2003

Si

1. Spanish for "yes".

2. Abbreviation for "suck it!"

3. Abreviatiin for "self injury"

Wy don't u si!

by Bojojo July 5, 2011

SI

1. Spanish for "yes."
2. Misspelling of "is."

1. "I suck." "Si."
2. "NO YUO FAGOT A COMPUTAR SI NOT A HAT!"

by Dj gs68 September 22, 2003

SI

self-injury

I haven't SI'd in two weeks.

by Anonymous Ex-cutter June 21, 2003

SI

SI is the abbr. of stupid idiot , although it can also be used in a way in which it means mug

I.E. billy you fucking si, si does not mean sigh which means you bore.

by jake lowe February 11, 2008

SI

Sisteme Internacional

SI units are the best, man. Inches suck.

by AnActualDefinition March 12, 2018