Lect

In sociolinguistics a variety, also called a lect, is a specific form of a language or language cluster. This may include languages, dialects, registers, styles or other forms of language, as well as a standard variety. The use of the word "variety" to refer to the different forms avoids the use of the term language, which many people associate only with the standard language, and the term dialect, which is often associated with non-standard varieties thought of as less prestigious or "correct" than the standard. Linguists speak of both standard and non-standard varieties. "Lect" avoids the problem in ambiguous cases of deciding whether or not two varieties are distinct languages or dialects of a single language.

Variation at the level of the lexicon, such as slang and argot, is often considered in relation to particular styles or levels of formality (also called registers), but such uses are sometimes discussed as varieties as well.

O'Grady et al. define dialect: "A regional or social variety of a language characterized by its own phonological, syntactic, and lexical properties." A variety spoken in a particular region is called a regional dialect; some regional varieties are called topolects, especially to discuss varieties of Chinese. In addition, there are dialect varieties associated with particular ethnic groups (sometimes called ethnolects), socioeconomic classes (sometimes called sociolects), or other social or cultural groups.

Dialectology is the study of dialects and their geographic or social distribution. Traditionally, dialectologists study the variety of language used within a particular speech community, a group of people who share a set of norms or conventions for language use. More recently, sociolinguists have adopted the concept of the community of practice, a group of people who develop shared knowledge and shared norms of interaction, as the social group within which dialects develop and change. Sociolinguists Penelope Eckert and Sally McConnell-Ginet explain: "Some communities of practice may develop more distinctive ways of speaking than others. Thus, it is within communities of practice that linguistic influence may spread within and among speech communities."

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