Establishing reference in Máíhĩ̵̀kì

In this dissertation, I investigate the hierarchical nominal lexicon of Máíhĩ̵̀kì, an endangered Western Tukanoan language spoken in northern Peruvian Amazonia. With data from original fieldwork, I establish eight types of nouns in Máíhĩ̵̀kì, each of which patterns distinctly from the others with respect to at least seven different morphosyntactic behaviors. I argue that these patterns can be predicted from the inherent semantic properties of the nouns, and provide a formal account of the parameters that govern the structure of the proposed hierarchy. In particular, I establish the notion of a `reference ratio'---the ratio of properties that are requisite to the entities in some set to the properties that are incidental of those entities. The first half of the dissertation provides an in-depth grammatical description of Máíhĩ̵̀kì. A chapter on Máíhĩ̵̀kì phonetics and phonology includes a detailed description of the language's nasal spreading and tone systems, and a chapter on Máíhĩ̵̀kì morphosyntax includes extensive treatments of deixis, event structure, and clause-linking devices. The latter half of the dissertation discusses the semantics of Máíhĩ̵̀kì nouns and nominal morphology. I provide a summary of the literature on nominal hierarchies, then argue for one such hierarchy in Máíhĩ̵̀kì based on the distinct morphosyntactic behaviors of nouns. I look at two of these morphosyntactic behaviors---the availability of plural morphology and the ability to be suffixed with or serve as a nominal classifier---in depth. A chapter on noun classification provides background on the typology of the phenomenon, including a discussion of the features of noun categorization devices common to northwest Amazonia. In addition to the typological survey, I provide a novel semantic analysis of Máíhĩ̵̀kì classifiers that has implications for the theory of both classification and nominal compounding. In a chapter on plurality, I provide a formal semantic analysis that addresses the complexities of number marking in Máíhĩ̵̀kì, including the availability of multiple pluralization strategies and their apparent optionality. The role of both classifiers and plurals in altering the reference ratio of nouns is examined throughout