r/etymology

I've figured out that gigas is supposed to mean like gigantic or giant, but where does regi come from? Does it relate to something with kingship?

I've figured out that gigas is supposed to mean like gigantic or giant, but where does regi come from? Does it relate to something​ with kingship?

I want to describe someone as capable of being a prodigy of everyone he meets. I tried to Google but I can't find a word. I'm going prodigal, which doesn't seem to be what I mean but it's the closest I can find. Maybe prodigomnent? Going off latin, but I'm having a hard time describing this in one word so any ideas are welcome