D[ra]kone -

There are two alternative scholarly theories as to the origin of the Slavs ethnonym, both very tentative: according to the first theory, it derives from a hypothetically reconstructed Proto-Indo-European *(s)lawos, cognate to Greek laós "population, people", which itself has no commonly accepted etymology. The second theory (forwarded by e.g. Max Vasmer) suggests that the word originated as a river name (compare the etymology of the Volcae), comparing it with such cognates as Latin cluere "to cleanse, purge", a root not known to have been continued in Slavic, however, and it appears in other languages with similar meanings (cf. Greek klyzein "to wash", Old English hlūtor "clean, pure", Old Norse hlér "sea", Welsh clir "clear, clean", Lithuanian šlúoti "to sweep").

Bernstein S. B., Очерк сравнительной грамматики славянских языков, vol. 1-2, Moscow, 1961.

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