QPR = QueerPlatonic Relationship.

This is a term that explicitly has a vague definition, because it is meant to encompass many things. That said, the definition I think is most useful is "a relationship which queers the culturally normative platonic relationship". Yes, this is broad, yes, it can apply to all sorts of folks and situations that probably don't use the term, and yes, it's not very explanatory by itself.

But. The point of this term is to be open to describing a lot of things for those who find it useful. Originating in a-spec communities, the idea of a QPR is typically a long-term, committed relationship that is not romantic, may or may not be sexual, and may be platonic, but not in a way that typical friendships are seen as.

For example: an aromantic person and an aro-spec friend of theirs are close. They intend to move in together, live together, and for all intents and purposes, make major decisions together which are typically viewed as things married couples do (like buying a house, moving for jobs, adopting pets). They do not feel romantic attraction to each other, but they wouldn't do this with just any friend of theirs. They have a close bond, and it's not really understood by a lot of folks around them, who may, depending on the genders of the individuals involved, be assumed to be (romantically) together and inept at romance, be together but poorly closeted, be poor poor bachelors who will never get a girl that way... all sorts of stuff, and a lot of the assumptions place a "that's not entirely platonic" bent on it. Thus: queer.

There's been debate about QPRs in all sorts of ways over the years, some in good faith, some not, some productive in exploring our assumptions, and some which deeply hurt and ostracized other members of our community. Some of these remnants of debates are popular to run into - some may refer to QPRs as halfway between romantic and platonic, some may insist that there should be a separate term for sexual or non-sexual QPRs (broadly, consensus was that this was an unacceptable division, redefining a term used to mean both from the beginning, usually a discussion in poor faith by either a sex-negative and/or sex-repulsed individual), and some may attack the way that this term doesn't require all individuals involved to be queer. Truthfully, my advice as someone who's identified as aromantic for a little over a decade?

Always leave space for people to have their terms, but never, ever enforce those terms on others. If a term is useful to the individual(s) involved, fantastic! If it fits them to a T, but they don't like it? Don't use it for them! Frankly, view that as similar to misgendering - they've now explicitly said they don't want to be called that. Just... be nice.