Two paths to polysynthesis

Abstract

West Circassian displays prominent polysynthetic morphology both in the verbal and nominal domains and both syntactic categories are subject to the same morphological ordering constraints. I argue that despite these similarities, nominal and verbal wordforms in West Circassian are in fact constructed via two distinct word formation processes: while the verbal root and any accompanying functional morphology are pronounced as a single phonological word by virtue of forming a single complex syntactic head via head displacement, the nominal head and its modifiers are pronounced as a single word due to rules of syntax-to-prosody mapping. Such a division of labor provides an account for why only nouns, and not verbs, exhibit productive noun incorporation in the language: West Circassian noun incorporation is prosodic, rather than syntactic. The evidence for the existence of these two avenues of word formation comes from a systematic violation of morpheme ordering observed in verbal nominalizations. In terms of broader theoretical impact, the proposed analysis provides insight into what factors shape a polysynthetic language: while it is tempting to reduce polysynthetic morphology to either simple head displacement or just a consequence of mapping complex syntactic structure to a single phonological word without any head displacement, the West Circassian data show that neither of these mechanisms can be dispensed with.