Ergativity

Morphological marking, whether realized by nominal case inflections or cross-referencing on the verb, can be either (i) ergative, marking transitive subject [A] function, vs. absolutive, marking intransitive subject [S] and transitive object [O]; or (ii) nominative, marking A and S, vs. accusative, marking O function. Absolutive is always the unmarked term in an absolutive/ergative opposition. Nominative is most frequently the unmarked term in a nominative/accusative system, but there are some languages in which accusative is unmarked. A language whose morphology mixes accusative and ergative marking has the split determined by (a) the semantic content of verbs, (b) the semantic content of NP's, (c) aspect/tense choice, or (d) a combination of these. A, S, and O are universal semantic-syntactic primitives. A universal category of ‘subject’ can be defined as the set {A,S}, and is valid only for the level of deep structure. Language-particular syntactic operations, such as coördination and subordination, work in terms of a (shallow-structure) ‘pivot’; this is most often S/A, but can be wholly or partly S/O (languages of the latter type are said to be ergative at the syntactic level). A major function of antipassive or passive derivations is to place A or O NP's (respectively) in derived pivot function, S. Many languages which have some morphological ergativity are entirely accusative (S/A pivot) at the syntactic level. All languages that show syntactic ergativity have some morphological ergativity.