Short for "cumulative audience", it's the total number of listeners a radio station has over the course of an
average week. Total amount of time
spent listening does not matter...if you listen to station A for fifteen minutes one day and station B three hours every day, you're still cumed to both stations.
If you regularly listen to three
radio stations over the course of a week, then you cume three stations, and
thos three stations would consider you
part of their cume.