Antipassive voice is a voice in an ergative-absolutive language in which:
- a noun phrase that normally has ergative case instead has absolutive case
- a noun phrase that normally has absolutive case is marked as an oblique or an indirect object, and
- the salience of the normally absolutive noun phrase is, according to some analysts, decreased.
Antipassive is a kind of valency decreasing operation that results in a very intransitive-like verb. The verb takes on the formal characteristics of intransitive verbs in that language.