Ergativity

An ergative–absolutive language, also simply called an ergative language, is a language in which the single argument ("subject") of an intransitive verb behaves like the object of a transitive verb, and differently from the agent of a transitive verb. This is in contrast to nominative–accusative languages, such as English and most other European languages, where the single argument of an intransitive verb (e.g. "She" in the sentence "She walks.") behaves grammatically like the agent of a transitive verb (e.g. "She" in the sentence "She finds it.") but differently from the object of a transitive verb (e.g. "her" in the sentence "She likes her.")

In ergative–absolutive languages with grammatical case, the case used for the single argument of an intransitive verb and the object of a transitive verb is the absolutive, while the case used for the agent of a transitive verb is the ergative. In nominative–accusative languages, the case for the single argument of an intransitive verb and the agent of a transitive verb is the nominative while the case for the direct object of a transitive verb is the accusative.

Examples of ergative–absolutive languages include Basque, Georgian and Mayan. There is a variant, ergative accusative languages, such as Dyirbal, which functions ergatively with respect to nouns, but nominative-accusative with pronouns.

An ergative language maintains a syntactic or morphological equivalence (such as the same word order or grammatical case) for the object of a transitive verb and the single core argument of an intransitive verb, while treating the agent of a transitive verb differently.

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