Extentsiooni

"Extentsiooni" is a term used as a variant or transliteration of the word "extension" in several languages and technical contexts. It generally denotes the notion of something being extended or the set of items to which a concept, function or object applies. The exact meaning depends on the disciplinary context.

In logic and philosophy of language, the extensional sense of a term or predicate refers to its extension: the collection of objects in the domain that satisfy the predicate. Extensionality principles, such as the axiom of extensionality in set theory, state that two collections are identical if and only if they have the same members. In semantics, contrast is often drawn between extensional (extension-focused) and intensional (sense-focused) descriptions.

In computing, the idea of extension appears in multiple forms: file extensions that indicate file type, software extensions or plugins that add functionality, and type or class extensions that expand behavior in programming. In mathematics, "extension" can describe enlargements of structures (field extensions, group extensions) that preserve or add properties.

Etymology traces the root to Latin extensio ("a stretching out"), which passed into modern European languages and technical vocabularies. Usage and spelling vary by language; "extentsiooni" may appear in transliterations or in languages that adapt the Latin-derived form. Related concepts include extensionality, intensionality, extension (semantics), and extension (mathematics).