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
The concept of inaccusativity is related to the broader topic of argument structure and grammatical relations