The Greek word for elements appears to be Stoicheia. Aside from ethnicity you could also go with Wu Xin, Godai, or Panchikarana.
The fifth element (not to be confused with the film) goes by aether, akasha, quintessence, or void.
I also spend a lot of time on Google Translate when I'm hunting for names. The Romanian word for essence, for example, is "esenţă", and for magic is "vrajitoare". The latter doesn't lend itself to much admittedly, but "Essenta" could work.