Placename glosses in the Samguk sagi
Chapter 37 of the Samguk sagi ('History of the Three Kingdoms', 1145) contains a list of place names and their meanings, from part of central Korea captured by Silla from the former state of Goguryeo (Koguryŏ). Some of the vocabulary extracted from these names provides the principal evidence that Japonic languages were formerly spoken in central and southern parts of the Korean peninsula.
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