Questionnouns

Questionnouns are a theoretical linguistic category referring to noun-like elements that carry an interrogative meaning and can form the core of an interrogative noun phrase in certain languages or constructed languages. The term is not widely attested in mainstream typology, where interrogative meaning more commonly arises through pronouns, determiners, or particles; questionnouns are discussed mainly in niche descriptive or conlang literature as a way to capture cases where an interrogative sense is packaged inside a nominal head.

In a language that employs questionnouns, a noun may bear inherent interrogative semantics such that phrases like “which X” or “what X” are built directly from the noun, sometimes with dedicated morphology or a separate question marker. This contrasts with systems where a separate interrogative word or determiner attaches to a noun phrase to signal questioning. Morphosyntactic alignment can vary: some theories propose that questionnouns decline for number or case, while others treat them as invariable heads modified by standard adjectives or articles.

Natural language usage of true questionnouns appears limited; many analyses prefer analyzing such forms as nominal interrogatives or as nouns functioning within an interrogative noun phrase rather than as a distinct, widely used category. Constructed languages, on the other hand, may implement questionnouns more explicitly to test how nominal heads interact with question morphology and discourse focus.

See also: interrogative pronouns, wh-words, nominal phrases, nominal classification, conlangs.