Definiálható

Definiálható is the Hungarian adjective formed from the verb definiálni with the suffix -ható, indicating possibility. It means that something can be defined, described, or specified by a definition, description, or rule within a given framework or language. The term is widely used in mathematics and logic, but also appears in philosophy, linguistics, and computer science.

In mathematics and logic, definability describes the existence of a formal description, typically a logical formula, that identifies a set, relation, or property inside a structure. A common formulation is: a subset S of a structure M is definable in M if there is a formula φ(x) in the language of M such that M ⊨ φ(a) iff a ∈ S. For example, in the real field with the usual operations, the set {x ∈ R : x > 0} is definable by φ(x) := x > 0. More generally, semialgebraic sets are definable by polynomial equations and inequalities.

Definability depends on the chosen language or structure; a set may be definable in one theory and not in another. In model theory, definability leads to notions such as definable sets, definable types, and definable elements.

In everyday language, definíható describes statements or objects that can be characterized precisely by a definition or rule, as opposed to being vague. The term emphasizes the possibility of formalization and precise characterization within a given framework.