The type of the hand gesture that royalty (for eg Queen Elizabeth II) gives when passing a crowd, normally from inside an expensive vehicle or on top of a horse drawn carriage. Similar to parade wave but with even less effort required, since everyone is already looking at royalty, there's no need to get their attention with large gestures.
It can be used by non-royalty to wave to a group of friends while a passenger in a car leaving a carpark or street, where it is normally intended as humor.
"I gave them the royal wave."
The art of sexually stimulating a woman with one's entire hand using a motion similar to that of the British Queen's famous wave. This technique is primarily used for women of the 'looser' variety, i.e those with a sizeable 'welly boot top'.
"Man, I was giving her the royal wave last night and I swear I still didn't hit the sides".