Precising

Precising definition is a type of definition used in the philosophy of language and linguistics to reduce vagueness by narrowing the meaning of a vague term within a specific context. It differs from a lexical definition, which documents ordinary usage, and from a stipulative definition, which assigns a new meaning for convenience. A precising definition adds a criterion of applicability that limits the term’s extension to cases relevant to a particular domain.

Practically, precising definitions introduce thresholds, boundaries, or conditions. They are contextual and not meant to apply universally. For example, the term poverty is vague in general use; in the context of a welfare program, a precising definition might specify a particular poverty line, such as an income threshold, or household size, used to determine eligibility. Another example is the term adult; for legal purposes, “adult” is precised as a person aged 18 or older, which determines rights and responsibilities such as voting or contract formation.

Precising definitions help communication and decision-making by reducing ambiguity where it matters. However, they can be controversial, as different contexts may justify different thresholds, and shifting definitions may affect who is included or excluded. They do not resolve vagueness in a term in all contexts, but instead tailor precision to a specific use.

Related concepts include lexical definitions, stipulative definitions, and the broader study of vagueness in language and semantics. Precising definitions are common in law, governance, and technical disciplines, where clear criteria are essential for rules, standards, and data interpretation.