My interpretation has always been that CONUS described a broad service footprint that served the majority of the CONtiguous (or CONtinental) US.
However, I consider the actual coverage area of a CONUS signal to be quite vague and undefined. It may or may not include Alaska, Hawaii, parts of Canada, Mexico or the Caribbean and it may not even serve all of the continental US fully. However, I believe what sets a CONUS signal apart from any other beam is that its service area is not restricted by any legal requirements nor is it purposely beamed to ONLY one specific region or locality.
In other words, your local channels on DN and DirecTV would be on SPOT BEAMS for your area only, but most movie and sports channels would be on a CONUS beam.
Al Jazeera on 97W would be a CONUS beam, but Cubavision on Hispasat 30W might not be able to legitimately call their service CONUS since they cannot reach all the states. They may just have to call it a "US" BEAM. Whether there are any set rules governing that, I don't know. But, I think that you understand how I perceive the CONUS signals as being rather loose and vague in this matter.
RADAR