An alternative definition is that language is a set of referents to a collectively constructed "picture" of reality. Wilfrid Sellars has done work on this. I s

An alternative definition is that language is a set of referents to a collectively constructed "picture" of reality. Wilfrid Sellars has done work on this. I say alternative because it shifts the focus away from person-to-person interaction and more towards impersonal social processes that construct what we think of as "objectivity". That's not to say what you're referring to isn't also an important part of the picture so to speak.