I can be mowing my lawn when it's 110F outside and say, "Gosh, I'm boiling." But if a recipe tells me to "boil" something, and it means anything other than put it in 212F water with heat applied in such a way that the water is bubbling, then the recipe is a shitty recipe, and I will diagnose the author with a confusion of the mind. The fact that the term now encompasses a much broader range of meaning in other contexts is completely irrelevant: I am not in those other contexts, in this context, it is a word with a very specific meaning.
The Slate article and this very HN discussion (broadly, not this sub-thread) are evidence that the phrase “caramelized onions” does not appear to have a singular, very specific meaning in this context. If it did, cookbooks wouldn’t make the claim and the Slate article and this discussion wouldn’t exist.
I can be mowing my lawn when it's 110F outside and say, "Gosh, I'm boiling." But if a recipe tells me to "boil" something, and it means anything other than put it in 212F water with heat applied in such a way that the water is bubbling, then the recipe is a shitty recipe, and I will diagnose the author with a confusion of the mind. The fact that the term now encompasses a much broader range of meaning in other contexts is completely irrelevant: I am not in those other contexts, in this context, it is a word with a very specific meaning.