The tag info for single-word-request indicates the difference between it and word-choice and vocabulary, but doesn't distinguish between it and terminology.
Why is Term for an event being referred to by its location or date tagged single-word-requests but Is there a term for referring to an organization by its city rather than by its name? tagged terminology? Is one of them incorrectly tagged?
The description for terminology says:
Topics related to the body of terms used with a particular technical application in a subject of study, theory, profession, etc.
I think the difference is that in one case, you are asking about a technical term, and when to use it (terminology); in the other case, you want to use a single word instead of a phrase, and you ask which word to use describing the context.
So, when you ask when the term metonymy is used, the tag should be terminology, but when you ask for a single word to use instead of "fantastic event that leaves you in a such catatonic state that somebody could steal the chair you are sitting on without you noticing it," that should be tagged single-word-request.
As you are referring to another question that is tagged terminology in your own question, I think it should be tagged with the same tag.
