Not really because FF isn't an obscure game series and is referenced everywhere, therefore in general people know that white mage tends to be a healer and black mage tends to be a nuker but you generally have to learn more to know more like with anything else in the world, and if someone is going to play an entry to a series especially without playing the games prior to it, you'd assume you'd want to learn about the series you're starting to play, just like you'd assume people to learn terminology and the like if someone were to play Mass Effect for the first time but started with 3 rather than 1.
Nope because outside of the FF world they mean nothing, but we are talking about Final Fantasy XIV, are we not?Is it so difficult to understand that outside of the whole Final Fanatasy world