Si

Is an abbreviation for Stupid Idiot, not to be confused with a nickname for someone called Simon.

You fucking Si; get 'ere now you Si

Si

the kinda deals that make you boogie

Si

SI

Sick Invite ( thank you for the non-invite )

You went for sushi!! SI (sick invite)

SI

In fanfiction, an acronym for self insert

He wrote a Pokémon SI story

Si

When you have no idea what the fuck your Spanish teacher is talking about.

: ¿Más preguntas?
: Si
:¿Cuál es la pregunta?
:Si

Si Wei

The ultimate hydro homie. He will drink your water if you're not careful

He's out of water already? His name must be Si Wei!

epic-sis-ity

A word used in the same context as epicness.

That place was overflowing with epic-sis-ity! Also see dubya speak