Linguistic distance

Linguistic distance is how different one language or dialect is from another. Although there is no uniform approach to quantifying linguistic distance between languages, the concept is used in a variety of linguistic situations, such as learning additional languages, historical linguistics, language-based conflicts and the effects of language differences on trade.

The proposed measures used for linguisitic distance reflect varying understandings of the term itself. One approach is based on mutual intelligibility, i.e. the ability of speakers of one language to understand the other language. With this, the higher the linguistic distance, the lower is the level of mutual intelligibility.

Because cognate words play an important role in mutual intelligibility between languages, these figure prominently in such analyses. The higher the percentage of cognate (as opposed to non-cognate) words in the two languages with respect to one another, the lower is their linguistic distance. Also, the greater the degree of grammatical relatedness (i.e. the cognates mean roughly similar things) and lexical relatedness (i.e. the cognates are easily discernible as related words), the lower is the linguistic distance. As an example of this, the Hindustani word pānch is grammatically identical and lexically similar (but non-identical) to its cognate Punjabi and Persian word panj as well as to the lexically dissimilar but still grammatically identical Greek pent- and English five. As another example, the English dish and German tisch 'table' are lexically similar but grammatically dissimilar. Using a statistical approach (called lexicostatistics) by comparing each language's mass of words, distances can be calculated between them. In technical terms, what is calculated is the Levenshtein distance. Based on this, one study compared both Afrikaans and West Frisian with Dutch to see which was closer to Dutch. It determined that the Dutch and Afrikaans (mutual distance of 20.9%) were considerably closer than Dutch and West Frisian (mutual distance of 34.2%). Besides cognates, other aspects that are often measured are similarities of syntax and written forms.

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