If I am correct, I readt it somewhere Esuna is a Japanese word. That was stuck in translations. I almost never use Esuna, cause I just only hate the word. In FFVI they say Remedy or Antdot, that is for me much clearer what it does. When I first saw Esuna I didn't knew what it did. I casted it on me and it didn't do nothing, so I didn't touch it for the rest of the game.