Joseph, I think even Gedolim would refer to a 13 year old as a boy and not a man.
Also, even according to the Torah, there is a difference between a 13 year old and a 20 year old, so the concept of adolescence is not completely foreign to Yiddishkeit. I think someone in that age range would probably be called a “naar” or “naara” in Loshon Hakodesh, a guy (if he’s a boy) in english, and a bochur or bochura in Modern Hebrew (although bochur and bochura would last till marriage I think).
It’s true – the one thing that is missing is a term in english for an unmarried girl above 12/18/20.