definiteness

Definiteness is a grammatical category of noun phrases that signals whether the referent is assumed to be uniquely identifiable to both speaker and listener, or not. It contrasts with indefiniteness, which introduces a non-specific or new referent. Across languages, definiteness is commonly marked by articles such as the definite article the in English, or by demonstratives, case marking, or pronouns when articles are absent.

In formal semantics, definite noun phrases are analyzed as denoting a unique individual that satisfies the noun’s predicate within the common ground. The definite reading presupposes that there is exactly one such individual, or at least that a salient one is identifiable in context. Indefinite noun phrases denote existentially quantified individuals without presupposing uniqueness. Some theories also allow context-dependent readings, where a definite description can project presuppositions about existence or uniqueness.

Languages vary in how they encode definiteness. Many have definite articles like English the or German der/die/das, while others rely on demonstratives or noun inflection, and some lack articles entirely, relying on context to convey definiteness. Definite marking often interacts with discourse, signaling familiarity, prior mention, or information status, whereas indefinites frequently introduce new or non-specific referents.

Cross-linguistic phenomena related to definiteness include the use of strong versus weak defi­­niteness, demonstratives functioning as determinants, and bare nouns in languages with little or no article system. The English definite article has historical ties to demonstratives, while the broader study of definite descriptions remains central in philosophy of language and linguistics, informing theories of presupposition, anaphora, and reference tracking in discourse.