Another simple question that I can't find an answer

How are gradients deleted? I think I'm finally beginning to be comfortable working with gradients, and now I'm in the habit of using inadvertently created gradients, by editing the stop colors, etc. But I have several images where there are literally more unused gradients than there are actual gradients in the image. I tend to be neat and organized, as much as possible, so I want to get rid of the gradients that end up not being used in the image. But I can't find how to delete them.
Surely there's a way?
Thanks for your always excellent advice
