Slang, referring to cocaine use and the white residue it leaves.
It can also be used to describe a look or action of a coke user.
Who left the ghostly prints on the mirror?
That chick at the coffee shop was acting ghostly, I think she is a cocaine user.
Is that guy a coke dealer? Yeah, he's my ghostly friend.
cool, awesome, when you really like something
that movie was ghostly