The meaning could be anything.
Medical:
number of flying hours etc.
i.e you can issue a JAA CPL licence with only 200 hours. If you want to fly commercially on a single man crew you have to have 500hrs Total time.
If you add you have an instrument rating this cancels out the 500 hrs. But having 200hrs with an instrument rating you cannot IFR more than 50nm, without the correct number of hrs.