I seem to remember hearing a radio interview or something and it was long ago so I admit in advance that I could be wrong. But I remember Burton saying that song writing is also the love of words whether it makes sense or not but it just sounds cool singing: hence Jezebel, Charlemagne, Jupiter, army, spears, etc.
Another example, is in Don't Bring me down by ELO the word "Bruce." That's my take--over and out! :-)