AB/C Tone Class Information of the Kohama Dialect for the Reconstruction of the Classified Vocabulary of Proto-Yaeyaman

In this study, we provide the tone class (AB/C) of 924 nouns of the Kohama dialect of Southern Ryukyuan Yaeyaman. As pointed out in Celik et al. (2022), there are very few reports on the tone class of each word in the different dialects of Yaeyaman. Furthermore, among the dialects (Kohama, Kuroshima, Yonaguni) known to retain the distinction between the tone classes B and C reconstructed in proto-Yaeyaman, the tone class of each word has only been extensively documented for Yonaguni. This means that, with the presently available data, the classified vocabulary of tone classes B and C reconstructed for proto-Yaeyaman is identical to the classified vocabulary of the present-day Yonaguni dialect. However, in order to achieve an accurate reconstruction of the classified vocabulary of tone classes B and C in proto-Yaeyaman, we need to compare the tone data from all the dialects of Yaeyaman that retain the distinction between these two tone classes. Accordingly, in this study, we focus on the Kohama dialect, which retains the distinction between tone classes B and C, and, on the basis of the authors’ fieldwork, provide information on the tone class of 924 nouns. With such data, we could also confirm that there is a regular correspondence between Kohama’s tone classes and the tone classes reconstructed in proto-Ryukyuan. That is, Kohama’s AB tone class corresponds to proto-Ryukyuan tone classes A and B while tone class C corresponds to the proto-Ryuykuan tone class C. However, some words belonging to tone class C seem to correspond to proto-Ryukyuan tone class B. Using the data, we hope to achieve a more accurate reconstruction of the classified vocabulary of classes B and C in proto-Yaeyaman.