The standard degree analysis of gradability in English holds that the function of degree morphology, such as the comparative, measure phrases, and degree adverbs, is to bind a degree variable located in the lexical semantics of gradable predicates. In this paper, I investigate gradation structures in Washo (isolate/Hokan), and claim that this language systematically lacks degree morphology of this sort. I propose that this gap in the functional inventory of Washo stems from a parameter on whether languages are able to introduce degree variables into the logical form that can be bound by such operators, providing further cross-linguistic support for a similar proposal made by Beck et al. (2009) for Motu (Austronesian). Specifically, I argue that gradable predicates in Washo do not introduce a degree variable. Consequently, if we assume that gradable predicates in English are type ⟨d, ⟨e, t⟩⟩, then Washo and English must differ in their lexical semantics for gradable predicates. Alternatively, if we want to maintain lexical uniformity between the two languages (i.e., that gradable predicates in English don’t themselves introduce degrees), then we must place variation at the level of a grammatical mechanism that introduces degrees in English for degree operators to bind, but which is lacking in Washo. The results of this investigation thus inform questions about the nature of cross-linguistic variation, specifically the division of labor between variation in functional categories and the lexicon. http://dx.doi.org/10.3765/sp.8.6 BibTeX info