When did people start using the term "target language" as it is used on this sub?

"Second language" / "L2" is limited because in many cases the language a person is learning is their third or fourth language, so I get why we would need a new term. I've heard "new language" or "additional language" as well, but I have mostly only seen "target language" used to refer to the language a text is translated/interpreted into, and not the language a person is learning. Reddit's algorithm started showing me this sub, and I keep seeing "target language" used in a way that I would consider nonstandard. After looking it up, it seems both definitions are accepted, but seriously, when did it come into fashion to refer to a language someone is learning?