Autonomy and heteronomy (sociolinguistics)

Autonomy and heteronomy are complementary attributes of a language variety describing its functional relationship with related varieties. The concepts were introduced by William A. Stewart in 1968, and provide a way of distinguishing a language from a dialect.

A variety is said to be autonomous if it has an independent cultural status. This may occur if the variety is structurally different from all others, a situation Heinz Kloss called abstand. Thus language isolates such as Basque are necessarily autonomous. Where several closely related varieties are found together, a standard language is autonomous because it has its own orthography, dictionaries, grammar books and literature. In the terminology of Heinz Kloss, these are the attributes of ausbau, or the elaboration of a language to serve as a literary standard.

A variety is said to be heteronomous with respect to a genetically related standardized variety if speakers read and write the other variety, which they consider the standard form of their speech, and any standardizing changes in their speech are towards that standard. In such cases, the heteronomous variety is said to be dependent on, or oriented towards, the autonomous one. In the terminology of Heinz Kloss, the heteronomous varieties are said to be under the "roof" of the standard variety. For example, the various regional varieties of German (so called "dialects"), such as Alemannic, Austro-Bavarian, Central, Eastern and Northern Hessian, Kölsch, Low German, and more, are heteronomous with respect to Standard German, even though many of them are not mutually intelligible.

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