Etymology: Thought to derive from "hardy"; any "RD" must be emotionally tough (and slightly stubborn) to deal with the fallout from her warring suitors.
"Yeah, I've never loved anyone like that before. Messes with your head. No idea what she did to me. Must be an RD."
Guy 2: Yeah, he sure is a real RD.
Friend 2 "What are you doing?"
Friend 1 "Sorry I had an R.D. moment."
Verb: 'I've been RDing at work today.', 'I RD'd some petrol from Texaco, didn't even pay for it.'