I wish there was a way to reclaim "diet", back to its meaning "what one eats" instead of meaning "what one eats to lose weight" (which really means what you can't eat). With the weight loss industry co-opting this word for their shell game, those of us who are trying advance fat acceptance are left out in the cold when trying to describe how we eat, and why we eat what we do for our own individual health re: allergies, pain management, illnesses, etc. I don't know how to go about reclaiming "diet", or what new words could be used instead as I am new to the whole fat acceptance/HAES movement, but what I have done when talking to friends/family about diets is qualify my diet as an HAES diet, and when they ask what that is, I explain the difference between eating to be healthy (and how I can eat what I want when I want, without guilt) and eating to lose weight. I explain that I don't diet, or exercise, to lose weight anymore, that what I do is designed for me to feel as good as I can, and be as healthy as I can, in the body I have, that I am done trying to force my body to be a size it wasn't meant to be and doesn't want to be. I don't know if this is any kind of solution, or if it would work for anyone else, but it seems to make some people think when they start talking diets, and I ask them to clarify what they mean by "diet", and then tell them that I don't believe in diets for weight loss and explain why.
And what I mean by the diet industry's shell game is that they know diets don't work, but they keep promoting diets, and coming up with new diets (which is really recycling the old ones, just giving them a new name). We are shown all these diets, each with its own little shell, and told try this, it will work. When that fails, it's "here's the next shell's diet, this one will work" and on and on and on, ad infinitum, as long as we are willing to buy into their game. And just like the con man's shell game, we walk away with less money, and nothing to show for it (except a temporary weight loss and extra pounds regained when the diet becomes impossible to follow forever). Touting a diet (for weight loss) as a lifestyle change is bullshit also. A lifetime of restricting calories, eliminating whole categories of foods, and eating exclusively low-fat, low-salt, low-carb, low-calorie everything is guaranteed to either starve you to death or make you go on an eating binge to assuage the hunger your body says you've been denying for far too long.
Personally, I prefer to eat a wide variety of foods, some healthy, some just delicious and maybe not so healthy, and do what exercise I can with the body I have. I'm not going to live my life wanting what I can't have, since I'm not thin now, never have been, and probably never will be. So be it, I'm working on loving me as I am, and living my life in the body I have now.