Drawing on Nietzsche and his own harrowing experiences in the concentration camps to which he lost his family, Viktor Frankl re-emphasized the importance of finding meaning of some sort in order to survive. We are meaning-needing creatures. I don't know that this is unique to us. Domesticated animals, at least, can become listless, bored, and depressed without some directed activity. Most of us have also seen animals in the zoo pacing a dirt-path in their enclosures perhaps because the activity toward which their lives would normally be directed or devoted have been taken from them.
We can give meaning to the world and to objects in it. This is more plausibly unique to us as a species. We are not only need-ers of, but also creators of, meaning. And, we can give meaning not just to words, but also to objects and places and any number of things. A trivial example: I have a small pebble, blood-colored and roughly in the shape of a heart. It has a meaning for me, though it of course has no meaning in itself, no natural meaning. (That's saying nothing more than objects in the world are not intentional unless they are given intentionality by semantic monsters like us.)
What I've been puzzling over recently is the difficulty of giving meaning to an object. The pebble for instance has a meaning that I gave to it, but I wasn't able to do that as a pure act of the will. It should be clear that I'm playing loosely with the notion of meaning, thinking about denotation and connotation and various other members of the family of meanings, but it seems to me in any case, an individual isn't enough to give something meaning. There's Wittgenstein's private language argument in the Investigations—unless there is no such argument to be found—but there's also a more general sense in which I think one individual cannot create meaning out of whole cloth. The pebble has the kind of meaning it does for me because of some of its own characteristics (shape, color, etc.) and the context of its being found by me while walking my dog Mateo and the subsequent events of Mateo's death shortly thereafter. None of these is sufficient for it to have any kind of meaning; though a human is necessary to give meaning even if—as in this case—the meaning is in a sense private—a meaning only for me—I don't think I could give whatever meaning I wished to whatever object or word or experience just by an act of the will, by fiat. That's the sense, it seems to me, in which the perhaps-illusory private language argument is correct: no individual by herself is sufficient to create meaning, because meaning has to be answerable to some other constraint in order really to be meaning.
Even in the case of language, I'm not sure that constraint has to be another language user.