I would like to understand the difference between Special Use Airspace (SUA) and Special Activity Airspace (SAA). I found the following definitions.
Eurocontrol Lexicon for SUA (from FAA):
Airspace of defined dimensions identified by an area on the surface of the earth wherein activities must be confined because of their nature and/or wherein limitations may be imposed upon aircraft operations that are not a part of those activities.
Eurocontrol Lexicon for SAA (from FAA):
[U.S.] Any airspace with defined dimensions within the National Airspace System wherein limitations may be imposed upon aircraft operations. This airspace may be restricted areas, prohibited areas, military operations areas, air ATC assigned airspace, and any other designated airspace areas.
Can you please help me to understand what the difference is?