The feeling of a sneeze building up in your nose and the satisfaction of it's release. Comparing the action, release and satisfaction you experience of a sneeze as to that of a sexual orgasm.
That sneeze felt so good it was like a nosegasm
When you have a plugged nostril due to a stuffy nose, but it suddenly clears out and you can breathe like a normal person for five minutes.
The best part about having a cold is getting to experience a nosegasm every morning.