Lately I've been finding
Dottie adorable as a nn, but not sure about
Dot. It's kind of cute, I guess, but a bit too wordy for me yet. Plus I have a Great Aunt
Dot (
Dorothy) so I sort of tie it to her. I think
Dot should have a full name, but it could work as a name on its own because of the word. You can detach it from
Dorothy and it becomes a modern little word name.