we are all very uncomfortable with the idea that it can't be defined

The trouble with explaining what queerness is (to your parents, to straight cis people, to your friends, to yourself) is that as soon as you define queerness as this or that, you have lost it. Once you pin queerness down and establish boundaries of what queer is and what it means, whatever that is isn’t queer anymore. It’s a solidified identity, which is precisely what queer isn’t. And so you have to go in search of the queer again. Every time you try to pin it down, it escapes you: that is queerness’ power. I won’t go so far as to say queerness is the search for the queer, but it is perpetually in motion. This makes people uncomfortable. Being queer can feel a bit like sea-sickness sometimes. Some people may even doubt the existence of the queer, given this notion of queer as horizon (as outlined by Jose Munoz). However, I would argue that unlike saying “Queer is…” saying “I am queer” does not limit queerness in a way that eliminates it. Instead, it enacts the notion of queer as horizon: it opens queer up to the infinite possibilities of your future. It understands your present as one of the possibilities of your past future. To say “I am queer” is not to say that queer is only what you are, but that you are an iteration which can and will expand queerness. You are a queerness which has never heretofore occurred, and all your potential is the realm of queer horizon of being. So the academic understanding of queerness does not destroy queer in lived experience. Queer continues to exist in the potentiality of queer-identified bodies. That is what, or where, queer is.
—  Haley Weaver, Enacting a Queer Ethic of Writing: Sometimes Y