I find people's desire to wrangle of the usage of words to their own version of correct endlessly entertaining. A lot of the time argument is entirely pointless as language drifts on its own even when powerful groups attempt to bash it into line in the way they want. Sometimes though small groups, when vocal enough, can change the way people talk in general - witness the way that gay is fading as a general pejorative term. (Obviously it is still used that way, but the pressure is on and the direction of movement is clear.) Of course for every term that people successfully add or change there are a thousand that people try for and fail at.
Witness the discussion about solopoly, a word that refers to people who practice polyamory without a primary domestic partner. That is, they date multiple people at a time with no intention of developing those relationships into live in partnerships. Even though I have read plenty about the topic and spend lots of time around poly people I didn't recognize the word when I saw it. I initially read it and assumed it was some type of poetry for some reason... you can parse it as 'solo + poly' easily enough but I didn't see that right away. I recognized the concept from a variety of sources but the language hadn't even reached me yet so it seems highly unlikely that it is an agreed upon term. The comments in the article I linked there had an interesting discussion about polyamory terms with plenty of heat on all sides.
One big thing polyamorous people argue about in that regard is the use of the term primary and secondary when referring to relationships. Some poly folk get really upset about that terminology because of the implication of hierarchy. They don't like the way the words can be used to imply that someone is of lesser importance. I don't generally use primary / secondary to describe my relationships but I don't have a problem with the words because I use them descriptively. Wendy is my domestic and romantic partner. If I say "I am moving to Edmonton" everyone would correctly assume that we are going together and made a joint decision. No one else in the world has such a role in my life and I think primary is a fine word to describe that.
The trick in this case is that I don't think that people with whom I have secondary relationships have an inherently subordinate position, nor do they require permission from someone 'higher up' to be there. I am not looking to fill primary and secondary slots, I am just describing the roles that people happen to have in the life I live. I certainly don't think that the primary / secondary description *does* fit everyone, much less that it *should*, but I can't deny that it is useful shorthand for my situation. I think this is a very common problem when small or new groups try to find words to describe themselves - some people use words descriptively, others think of them prescriptively, then trouble starts.
There is an argument made that primary / secondary designations cause people to treat secondary partners badly and to think of them as being under the authority of the primary. This dynamic can play out like "Sorry, my wife told me I have to break up with you because she finds you irritating" and that is, to me, a disastrous relationship model. I don't think it is the words that cause that though, rather it is that people are sometimes total jerks and they use language to try to defend their bad behaviour.
Words are hard. However, I think that they become less conflict ridden if people remember to keep "This generally conveys the right information" and "This defines you completely" separate in their minds. Acknowledging that descriptive vs. prescriptive interpretations are quite different and that which we are talking about should be decided up front avoids a lot of arguments.