Some northern Panoan languages have an unusually high level of synonymy distributed nonrandomly in their lexicons. Matses, for example, has as many as five synonyms for most game animals. This synonymy clearly is not solely a product of incidental linguistic factors such as transitional diachronic lexical changeover. While word taboos, mutual intelligibility, group identity, and incorporation of captives may have contributed to the genesis of these game synonyms, the elaboration of this phenomenon appears to be primarily the product of conscious manipulation of the lexicon to serve cultural purposes, primarily that of providing a means of publicly displaying hunting knowledge.