Translating Terms of Art
The English phrase “term of art” is nicely self-referential, because it is one. A “term of art” is a term — a word or a phrase — that is used technically in a narrow context. It usually has nothing to do with “art,” except in the now antiquated sense in which “law,” “science,” etc. are all “arts.”
In addition to their specific meanings, terms of art are generally frozen phrases. So, for example, “art term” doesn’t mean at all what “term of art” means (even though “art work” is a lot like “work of art”).
Terms of art create a double translation challenge (as, really, does everything that is to be translated). They have to be identified and understood, let’s say in Greek, and then rendered accurately in translation, say, in English.
As is frequently the case, an example from modern languages may help demonstrate the point. (I’ll use American English and Israeli Hebrew only because I happen to speak those two languages.) In English we have a phrase “third party,” as in, for example, “third party liability insurance.” In Hebrew, that’s called tzad gimel, literally, “side gimel,” (gimel is the third letter of the Hebrew alphabet.)
(The “third party” is someone injured by the insured who is not a party to the insurance contract. The insured is the “first party” and the insurer is the “second party.”)
Translating tzad gimel into American English requires knowing something about the insurance industries in Israel and the U.S., in addition to a familiarity with the terms of art in the two languages.
These facts also mean that the Hebrew tzad should usually be translated “side,” but in certain narrow contexts, the only right translation is “party.”
In fact, tzad gimel is an easy case because English has a matching term of art.
What happens when the target language doesn’t have anything that matches the original?
I think that sarx and simeion are two good examples.