A “ruined orgasm” is when someone — usually a man, but this can be done with women too — is brought to the edge of orgasm and then, the moment they start actually orgasming, stimulation is ceased. This can sometimes cause light pain — it has something to do with the lack of neurological and physical stimulation usually associated with the orgasm itself.
Liana Good is known for these. Here’s another good example.
Often when you watch a video of one of these, the woman will be holding the man’s penis while he orgasms, but not providing stimulation. Like so:

(I put in a screenshot because not everyone can view Redgifs content due to age verification laws.)
Here’s the interesting thing, though: I’ve done these before, both solo and with other people, and while it does cause a little discomfort, I find it to be a good discomfort. I’m a bit of a masochist, as I’ve said in the past, and a little pain doesn’t ruin an orgasm for me. I don’t like the whole power exchange thing — I like to be in charge even when I’m doing something that is “traditionally” considered a submissive activity, like this, or having my face sat on, or being pegged or spanked. I just like the different sensations. And receiving a ruined orgasm is definitely a different sensation.
If you’ve never tried one, it’s worth it, just to see if you might like it. For men or women, I can tell you it’s definitely more effective if you edge for a while first, although honestly the more you edge the bigger your orgasm is anyway so that’s always a fun additional activity.
Now you know.
