look up any word, like sparkle pony:
 
1.
A phrase used when you agree with something someone says. Usually spelled say tht, say dat && say dhat.
It's basically just a shortened way of saying 'you can -say that- again'. Not to be confused with say that then.
Tori: I'm so tired of skanky ass hos, close ur damn legs and get some class. please

Aunjel: Mhmmm. Say dhat. :)

Rachelle: Truth. Say that girl.
by Tori-<3 October 04, 2010
 
2.
A phrase used to agree with a statement. Oftenly used by moronic dipshits that have no vocabulary at all.
"Dude, I'm sooooooooo zoo'd right now"

"Say that! Me too"
by Epik kid July 26, 2009
 
3.
A phrase used after saying a random and/or fake word (that doesn't exist) simply for the purpose of making someone else start the habit of using "say that!"
- Le'mon (lemon in a French accent) ... Say that!

- Lemon.

- No, le'mon - in a French accent.

- Le'mon.

- Good.