look up any word, like hipster:
 
1.
To understand something.... to confirm a statement. To agree with someone. Another way to say "I feel you"

*Mostly used by people from the West Coast
Mark: Hey are you trying to ball later?
Anthony: Oh yup! I speak that("I feel you")

Anthony: Are you trying to go to this party later?
Mark: I speak that!
Anthony: You speak that?
Mark: Oh yup! I speak that!
by WildcatChick December 13, 2010