Word meaning is relative to a language. The neo-Gricean thesis that word meaning is recursive, conventional, cogitative speaker meaning holds only for living languages like English. Related theses hold for dead languages and idiolects. Word meaning is determined by stipulation rather than by convention in artificial languages (at least initially), by individual custom in idiolects, and by prior practice in dead languages. What we can say in general is that word meaning is “established” speaker meaning. This chapter distinguishes the different ways in which speaker meaning may be established by examining different types of languages. We will focus on the convention-dependence of living natural languages and on the linguistic lineages that their evolving conventions create. The self-perpetuation of conventions coupled with linguistic diversity has generated thousands of genetically related natural languages in much the same way that reproduction and individual variation have generated millions of genetically related biological species. Natural languages are discovered when a community is found that has a previously unknown set of linguistic conventions. What words mean now in a living natural language is determined by the current lexical and constructive conventions of those speakers whose conventions have evolved from the conventions of prior users of the language. This will enable us to avoid the apparent circularity inherent in saying that English is defined by the conventions of English speakers.