What makes a noun “unmarked”? Thematic distribution of case in Niuean and Māori

This squib considers what it means for a noun to be “unmarked” in terms of its morphosyntactic case (e.g., nominative, absolutive, ergative, accusative). In typological literature, the “unmarked” argument of a language is the argument with nominative or absolutive case (Dixon, 1979). In syntactic literature, it is recognised as being the argument most accessible in terms of syntactic dependency operations, such as movement (i.e., it can undergo extraction; Otsuka, 2006; Deal, 2017) and verb agreement (i.e., its features can be indexed on the verb; Bobaljik, 2008). However, the term “unmarked” has thus far evaded a straightforward explanation in linguistics (Haspelmath, 2006), and often is adopted without definition. The goal of this squib is to develop such a definition, drawing on the patterning of ergative, absolutive, nominative and accusative cases, with a focus on Niuean (ERG-ABS) and Māori (NOM-ACC). I put forth the view that case markedness is best characterised as a distributional attribute of language, where “unmarked” corresponds to the case value consistent with the widest array of different thematic roles assigned by a verb or predicate to its core arguments (agent, experiencer, patient, goal).