At what point does he become my boyfriend?

So this person I’m seeing has referred to what we are doing as a long-distance relationship and has referred to us as a couple. (We’ve been friends for years but have escalated romantically pretty recently lol). I’m calling him my boyfriend but not in front of him

Does “relationship” or “couple” or both or neither make him my boyfriend?

I’m going to bring it up soon, but I want to know if I’m way off base or what the general understanding of it is.