Earlier quoted context omitted.
> This places pendants like me at a serious disadvantage; I can't rely on a dictionary to help me win arguments about correct usage. I feel like you're being sent a strong signal about what "correct" means re usage but refusing to heed it. Dictionaries aren't descriptivist because of an idealogical commitment or whatever; a strictly prescriptivist stance is simply not very useful for achieving the goals that a dictio…
> simply not very useful for achieving the goals that a dictionary has. Apparently the dictionary's goals are not the same as my goals. Sure, I want to know about incorrect usages; but I also want to know that those usages are incorrect .
Say that an English speaker speaks a sentence, and an English listener understands it. If they both agree that it was an English sentence -- including no jargon -- and they both agree on the meaning of the sentence, then that's correct English. If the two individuals have also never met before, then it's certainly correct English.
That's what "defined by usage" means. English does not have a language regulator or language academy.