noun /ɜː(ɹ)ˈɡə.tɪv.ɪ.ti/
A structuring property of the grammar of certain languages consisting in the differential treatment given to A (the subject of transitive verbs), in contrast to O (the object of transitive verbs) and S (the subject of intransitive verbs), which are treated similarly. This differential treatment may take the form of a special case marker (e.g., an affix or a particle) used with A but not with O or S, or of a specific agreement pattern (e.g., the verb may agree in person and number with A, but not with O and S).
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