When I was coming of age, to cum was to have an orgasm... they were the same. The first time I heard them as being seperate is when I was dating a girl who would say, 'yeah.. I had an orgasm... but I didn't cum.' She's the only person I've ever heard, until now, describe them as different. I think cum is synonymous with orgasm... not with ejaculation. My wife ejaculates (squirts) sometimes during an orgasm, but squirting or no, she calls it cumming.