text: In grammar, the ergative case (abbreviated ) is the grammatical case that identifies a nominal phrase  as the agent of a transitive verb in ergative–absolutive languages.
  Characteristics
  In such languages, the ergative case is typically marked (most salient), while the absolutive case is unmarked. Recent work in case theory has vigorously supported the idea that the ergative case identifies the agent (the intentful performer of an action) of a verb.