Dialect levelling

Dialect levelling or dialect leveling refers to the assimilation, mixture and/or eradication of certain dialects, often due to language standardization. Dialect levelling has been observed in most languages with large numbers of speakers after the industrialization and modernization of the area or areas in which they are spoken.

Dialect levelling has been defined as the process by which structural variation in dialects is reduced, "the process of eliminating prominent stereotypical features of differences between dialects", "a social process [that] consists in negotiation between speakers of different dialects aimed at setting the properties of, for example, a lexical entry", "the reduction of variation between dialects of the same language in situations where speakers of these dialects are brought together", "the eradication of socially or locally marked variants (both within and between linguistic systems) in conditions of social or geographical mobility and resultant dialect contact", and the "reduction...of structural similarities between languages in contact", of which "interference and convergence are really two manifestations".

Leonard Bloomfield implicitly distinguished between the short-term process of accommodation between speakers and the long-term process of levelling between varieties, and between the social and the geographical dimensions. On the geographical dimension, levelling may disrupt the regularity that is the result of the application of sound laws. It operates in waves, but may leave behind relic forms. Dialect levelling and Mischung, or dialect mixing, have been suggested as the key mechanisms that destroy regularity and the alleged exceptionlessness of sound laws.

Dialect levelling is triggered by contact between dialects, often due to migration, and has been observed in most languages with large amounts of speakers after the industrialization and modernization of the area or areas in which they are spoken. It results in unique features of dialects being eliminated and "may occur over several generations until a stable compromise dialect develops." It is separate from levelling of variation between dialectal or vernacular versions of a language and standard versions.

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