What is the term for using an adjective in the place of a noun?
It seems to come up a lot in fantasy fiction, generally used as a proper noun to describe a group ("the Twisted", "the Hunted"), but it also comes up in everyday use ("the mentally ill").
Grammatically, Quirk, Greenbaum, Leech and Svartvik (1985) describe this as adjectives functioning as heads of noun phrases' (7.23—7.26, pp 421—424).
Rhetorically, this is a combination of ellipsis (the omission of a word or phrase which is easily understood in context) and metonymy (referring to something or someone by one of its/their attributes).
