Instrumental case

In linguistics, the instrumental case indicates that a noun is the instrument or means by which the subject achieves or accomplishes an action. The noun may be either a physical object or an abstract concept.

For example, in this Latin sentence:

libros stylo scripsi.

the inflection of the noun indicates its instrumental role -- the nominative stylus changes to stylo. English, lacking an instrumental case, might use a preposition (usually with) to express the same meaning:

I wrote the books with a pen.

The instrumental case appears in Old English, Sanskrit, and the Slavic languages; in Latin, it appears as the ablative of means.

Instrumental case

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