When is it better to use a generic term rather than a specific title when referring to fantasy elements in worldbuilding?

Question

Something I've noticed when worldbuilding fictional setting is that there are generally two distinct ways of referring to fantastical elements in a story.

1. Using a general descriptor with broadly-understood language that explains what the thing is in layperson's terms
2. Using a word or phrase that gives a very specific name or title to the object or phenomenon being discussed

Two examples I can think of that I noticed in recent fiction (both from urban fantasy series) are as follows...

• In some works magic spells are referred to as "sleep spells" or "fire spells" or whatever, versus other works that give them specific names like a "Somniosus" or something like Harry Potter's spell names (Wingardium Leviosa, Avada Kevadra). The same is true with magical artifacts and other supernatural phenomena.
• In an unpublished work that discussed the societal office of a person whose job it was to police the supernatural and keep it hidden, the author was debating whether to refer to the position in very general terms (i.e., regional head) or give the post a specific title and use that throughout the story (e.g., marshal, praetor, or something like that).

I was mostly wondering when it was appropriate to use more generic descriptor names versus more specific names. More generic names can be useful because readers will intuitively know what a "sleep spell" or "regional head" does, and people to tend to talk in that manner, but on the other hand people often will use specific terminology when discussing something, especially if the meaning of that term is well-understood.

Answer 1

This is the classic reason why so many stories open with someone new, who has to learn the terms: so the readers can pick them up easily.

But you should put the point of view entirely within the character and use that character's terminology. Making clear what they mean is often an art in itself, and most readers will forgive a few cheats toward it, such having to explain for weak reasons.

Answer 2

Both approaches are valid, and neither need be used exclusively in any given piece of writing.

Whenever you have an unfamiliar term to deal with - be it a made up fantasy word, a term from a foreign language, or a historical word that's fallen out of use - you have a choice: do you use the obscure word, or do you replace it with a modern English equivalent?

If you use the original word, you deliver a more immersive experience to the reader, but you also give yourself the job of explaining (one way or another) what that word means. So there's a benefit and a cost to that approach. Alternatively, you can stick with generic modern English, making your work easy to understand but with the danger of being more bland.

So the question you have to answer in each case is "is the benefit I'm going to gain worth the cost?" If your regional head is only going to make a fleeting appearance in your story, perhaps mentioned just once or twice by a character, it might not be worth the investment of giving them a specific title and explaining that it's equivalent to "regional head."

Another thing to consider is that there might be things that mark out your specific case from the generic one. The two terms mean broadly the same thing, but there's a world of difference in tone and nuance between Regional Head and Gauleiter!