So I found my French to English dictionary the other day and Godric was looking at it and I told her to look up Vol. I already knew that mort means death.
Vol means flight. So Voldemort means 'Flight from Death' or 'Flight of Death'. That's so fitting!
I wonder if JKR thought of the name Voldemort first or Tom Marvolo Riddle first? I'm betting on Voldemort because it means something in French.