The distinction between the major lexical categories of noun, verb and adjective figures into myriad linguistic generalizations and has been a center of gravity in the study of language since antiquity. Notwithstanding their importance, lexical categories are poorly understood (see e.g. Baker & Croft 2017). Outstanding is whether there are generalizations about the meanings words in the major categories have. Many have claimed there are, and proposed theories linking meaning and category, in a one to one fashion. Such theories have been criticized, however, in light of clear counterexamples, and consequently the search for a universal link between meaning and category is perceived by many to have been unsuccessful (see von Fintel & Matthewson 2008). This project recasts the search for a link, in the spirit of recent work (Francez & Koontz-Garboden 2017: Chapter 5), not as one for a one-to-one mapping, but for constraints on meaning induced by category. The project targets a domain where the set of relevant meanings is small, but where there is variation in category: property concept sentences—sentences like (1) He is very clever, whose main predicate is an adjective or, (2) akwai shi da waayoo `He is very clever (lit: He exists with cleverness; Hausa; Newman 2000:179)', whose main predicate is not an adjective, but is translated by a sentence whose main predicate is an adjective in languages with a large class of them. Although (1) and (2) have the same meaning, their component parts do not.
We have found that while an abstract mass-type meaning is restricted to nominal property concept words, a predicative type of meaning can be found across noun, verb and adjective. Furthermore, we have shown that the contrast between this meaning type is deep, and can be found at the level of the root, as exemplified by our work on Washo, which has shown that the same language shows both meaning types in different root classes. We have additionally found that there are categorizers crosslinguistically that can turn abstract mass-type roots into predicates of individuals of all major categories---noun, adjective, and verb---a consequence of the possibility of the semantics of possession being packaged with functional heads which categorize roots as noun, verb and adjective. Property concept words across all these categories can be found behaving as if they have a semantics of “degree”, though evidence suggests that the degree-related meaning comes not from the open class noun/adjectives/verbs, but rather from functional vocabulary. Internal to the category of verb, a crosslinguistic survey of state/change of state derivation shows that verbal states are more likely to be polysemous with derivationally related change of state predicates than nominal or adjectival ones, a fact which is attributed to verb being the only category that can describe changes of state.
