Usage note: In linguistics dialectal, not dialectical, is the term more commonly used to denote regional or social language variation: Dialectal variation is more marked in the South than elsewhere in the United States. In general writing either term may be found.
A regional or social variety of a language distinguished by pronunciation, grammar, or vocabulary, especially a variety of speech differing from the standard literary language or speech pattern of the culture in which it exists: Cockney is a dialect of English.
A variety of language that with other varieties constitutes a single language of which no single variety is standard: the dialects of Ancient Greek.
The language peculiar to the members of a group, especially in an occupation; jargon: the dialect of science.
The manner or style of expressing oneself in language or the arts.
A language considered as part of a larger family of languages or a linguistic branch. Not in scientific use: Spanish and French are Romance dialects.
[French dialecte, from Old French, from Latin dialectus, form of speech, from Greek dialektos, speech, from dialegesthai, to discourse, use a dialect : dia-, between, over; see dia- + legesthai, middle voice of legein, to speak; see leg- in Indo-European roots.] di'a·lec'tal adj., di'a·lec'tal·ly adv.
Synonyms: These nouns denote forms of language that vary from the standard. Dialect usually applies to the vocabulary, grammar, and pronunciation characteristic of specific geographic localities or social classes. The vernacular is the informal everyday language spoken by a people. Jargon is specialized language understood only by a particular group, as one sharing an occupation or interest. Cant now usually refers to the specialized vocabulary of a group or trade and is often marked by the use of stock phrases. Argot applies especially to the language of the underworld. Lingo is often applied to language that is unfamiliar or difficult to understand. Patois is sometimes used as a synonym for jargon or cant, but it can also refer to a regional dialect that has no literary tradition.