Nominative-absolutive

Nominative-absolutive alignment is a form of split-ergativity in two ways. The first split is internal to the clause type, which presents both nominative and absolutive morphological patterns with no corresponding accusative or ergative patterns: most present no nominal case-marking (although in two of the languages described here, free pronouns can be used only for nominative arguments); where there is auxiliary agreement, it is always with the nominative; absolutive pronominal enclitics mark the main verb. The label nominative-absolutive follows from the absence of a distinct marked accusative or ergative pattern. The second split is based on tense-aspect-mood-polarity, in which the nominative-absolutive clauses code future, imperfective, irrealis, and negative. These patterns are both counter to the expected universal patterns identified in the typological literature: no other cases have been identified in which case-marking is nominative while verbal cross-referencing is absolutive, and the universally expected semantic values of the ergative clause type are, respectively, past, perfective, realis and positive. We conclude by asking if the number of counter-examples to putative universals of split ergativity should lead us to question the validity of the definition for the typological category “ergative construction”.