The notion of something being a "fake" seems linguistically odd. Normally, if you have an adjective and a noun, the noun notes what the thing being talked about is, and the adjective describes some quality of the thing in question. A "fake plant", however, doesn't seem to fit that pattern at all, because a fake plant isn't a plant to begin with; the noun seems to be violating its intended function. Is "fake" something other than an adjective, then, perhaps analogous to "not a"? Or is a "fake plant" actually a "fakeplant", i.e. the fake is a part of the noun rather than an adjective, despite its apparent form? Doesn't the adjective "fake" somehow undermine the purpose of nouns?

I'm having trouble confirming it online at the moment, but I believe that linguists have a category for words such as fake, artificial, would-be, and the like: I think they're called "cancelling modifiers" or "cancelling adjectives." These words are well-known exceptions to the rule that, given an adjective A and a noun N, any AN is an N. I don't think they "undermine the purpose" of nouns or adjectives; instead, they perform a special and useful adjectival function in language. Anyway, you might search for information on the linguistics of cancelling modifiers or cancelling adjectives. I hope you find the clarification you're seeking.

One point worth noting here is that words like "fake" are, so far as I can see, always intensional. meaning that whether something is a fake F depends upon what property F is, and not just which things are F. They are also "attributive", meaning that an Adj-Noun isn't just an Adj that is Noun, but (roughly) something that is Adj for a Noun. E.g., a tall basketball player is someone who is tall for a basketball player, not just someone who is tall and a basketball player. Attributives are hard enough; intensionality is hard enough; both by themselves. Put them together, and it's a nightmare.

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