Instrumentaalsest

Instrumentaalsest is a linguistic term used to describe the instrumental function in grammar—the relation that marks the means or instrument by which an action is performed. The concept is central to discussions of how languages encode instrumentality and means in clause structure.

In languages with a dedicated instrumental case, nouns or pronouns morphologically mark the instrument. The instrumental case typically answers questions such as "with what?" or "by means of what?" and often coexists with other case functions that mark time, location, or agency. The exact form of the instrumental case varies across languages, affecting noun endings and pronoun inflections.

Where there is no separate instrumental case, instrumental meaning is expressed through prepositions, postpositions, or periphrastic constructions. For example, in languages with rich case systems, the instrumental may appear as a distinct inflection; in other languages, instrumental meaning is conveyed by words meaning "with" or "by means of" attached to the noun phrase. Cross-linguistically, instrumental marking can also overlap with comitative or instrumental-adjunct functions, depending on the language.

In Estonian-language linguistic discussions, the instrumental function is often described with the term instrumentaalsest. In practice, Estonian commonly expresses instrumentality using postpositional forms or prepositional phrases, such as with the suffixes or particles that attach to a noun to denote "with" or "by means of." For instance, a phrase meaning "with a pencil" is formed by combining the noun with an instrumental marker. Overall, instrumentaalsest serves as a focal point for comparing how languages encode means, tool use, and method within sentence structure.