Definitions by mat a

s.i.s 

Means to "sit in silence" insetad of lol. Usually used if somebody sais something retarded online, its a good way to be honest. Lets face it very few actually laugh at stuff online.

xXihateyouxX: i was like "duhhhhhhh" haha
ay u guys 2003: s.i.s

s.i.s by mat a April 24, 2005