A variety of language having some basis within a community. An acrolect is a variety associated with prestige (e.g. BBC English); a basilect is the reverse; dialect is regional variation, and genderlect is difference of speech based on the gender of either speaker or hearer. An idiolect is a personal dialect. It is regarded as important in the philosophy of mind and language not to think of a public, shared language as simply a number of coincident idiolects, but rather as something prior, from which idiolects are derivative.