Don't feel bad.
I had to have it explained to me too.
I have since learned also - that it is another one of those terms that can mean either good (cool stuff) or bad (stoopid stuff).
Kinda like - "Yo, that ride is BAD"
Or "that girl is Phat" (not fat)
And to think we drove our parents nutz with some of OUR slang.
I am much to young to feel this dang old.