Centum-Satem isogloss

The Centum-Satem division is an isogloss of the Indo-European language family, related to the evolution of the three dorsal consonant rows reconstructed for Proto-Indo-European, * (labiovelars), * (velars), and *; (palatovelars). The terms come from the words for the number "one hundred" in representative languages of each group (Latin centum and Avestan ).
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