To hide or
dispose of something in such a way that it will be extremely difficult or impossible to find or recover, even for the person doing the hiding. Get rid of.
Nautical in origin, it comes from a call indicating a depth of six fathoms (over ten meters), a depth from which recovery of an item tossed
overboard would be very difficult.
Argggh, matey!
Deep six the crack pipe before Admiral
Billy-Bob catches us.
Jimmy-Joe, we'd better
deep six the whole meth kitchen before
Andy Taylor shows up at the trailer park