ICAO ATC Comms Doc 4444 defines "orbit" as a delaying tactic when in the vicinity of an airport. It can therefore be given at any stage when close to an airport and does not have to be IFR only. I have orbited some of the finest airports in the world - prior to holding area, during intermediate approach and on an ILS and non-precision approach and had VFR traffic orbit downwind for my benefit!