benefactive

Etymology
From plus. Attested since the twentieth century.

Adjective

 * 1)  Of or pertaining to the linguistic form or case or the semantic role of the beneficiary of an action. Expressed in English as "on behalf of" or "on one's behalf."

Noun

 * 1) A term or sentence element that serves a benefactive role or that is inflected for the benefactive case or a similar case (such as the ).