Inaccusative

Inaccusative is a linguistic phenomenon observed in some languages where the grammatical subject of an intransitive verb is treated differently from the grammatical subject of a transitive verb, and is instead treated like the direct object of a transitive verb. This means that the subject of an intransitive verb, which typically denotes the single participant in an event, behaves in certain grammatical respects as if it were the patient or undergoer of an action, rather than the agent.

Languages that exhibit inaccusativity often use distinct grammatical markers or syntactic constructions for subjects of intransitive verbs that describe states or changes of state, compared to subjects of intransitive verbs that describe actions. For instance, in many inaccusative languages, the subject of intransitive verbs like "die" or "arrive" might be marked with the same case as the object of transitive verbs like "see" or "hit", while the subject of an intransitive verb like "run" or "sleep" is marked differently, often with the same case as the subject of a transitive verb.

The concept of inaccusativity is related to the broader topic of argument structure and grammatical relations in linguistics. It highlights the diverse ways languages categorize and mark participants in events. Understanding inaccusativity helps linguists analyze the underlying semantic roles and their syntactic realization across different languages. It is a key feature in the study of ergativity and the typology of verb-argument systems.