A Chakobsa term, the language of the Fremen people in Frank Herbert's Dune book series, that translates to "The Voice from the Outer World". The term refers to a visitor from another planet who would lead the Fremen to paradise, a prophecy implanted by the Bene Gesserit witches to control the Fremen. Paul Atreides / Paul Muad'Dib takes up the title in the first book in the series.
He knows our ways as if born to them, he must be the Lisan Al-Gaib!
The particular day of the week in which the mass gathering of Big Nigga and his disciples commences, occurring always on the second day of the week. This weekly meeting occurs to allow Big Nigga to bring new gifts and lessons to his followers.
"Did you hear what happened last Big Nigga Tuesday? I heard Big Nigga showed the crew how to eat a Big Mac!"