(pronounced like "slay") Literally means Smiling Like An Idiot. A term to be used for those times when you can't help but have a stupid grin on your face. Usually used in the positive sense. Used very much like the term "lol"
Person 1: Hey, I hear you're going to the movies with Chris tonight.
Person 2: Yeah (with that idiotic grin)
Person 1: You are so slai.
OR
If you were in class, and it was a very inappropriate time to laugh, you might be slai.
Person 2: Yeah (with that idiotic grin)
Person 1: You are so slai.
OR
If you were in class, and it was a very inappropriate time to laugh, you might be slai.
by Tesla15 September 22, 2012