Actually, the definition goes beyond whats listed in the CFS:For the purpose of the legislation at hand, the fact that an aircraft could land somewhere is irrelevant. The only locations that matter are those listed/registered in the NAVCANADA Canada Flight Supplement and/or Canada Water Aerodrome Supplement.
aerodrome means any area of land, water (including the frozen surface thereof) or other supporting surface used, designed, prepared, equipped or set apart for use either in whole or in part for the arrival, departure, movement or servicing of aircraft and includes any buildings, installations and equipment situated thereon or associated therewith; (aérodrome)
This is straight from the Aeronautics Act. As you can see, there is nothing that references "registered with the CFS"