Actually, I think that the correct answer is single quotes. Double quotes are used for quoting a statement by someone else: -> Bill said, "I love pizza."
In the context of this web-site,
this is used to indicate code. It has no proper use in normal prose.
Block quotes are for... well blocks of quoted text, usually from previous posts
bold is loud emphasis, e.g. a raised voice, while italics is for adding intensity to a word or phase.
Single quotes are references to the word in its general role, not as a part of the enclosing sentence, i.e. separated from semantics. To use your example:
Does the word 'cheese' indicate something yellow?
The word 'cheese' is no longer food in the sentence. It is a word. You can put any word in this sentence and it would still be proper.
Does the word 'run' indicate something yellow?
Does the word 'as' indicate something yellow?
Does the word 'preposterous' indicate something yellow?
In all cases the term in the single quotes has the same function in the sentence, no matter whether the word itself is a verb, noun, adjective, or whatever. In this sentence all are words, i.e. nouns because they are references indicated by single quotes.