Middle Korean ㅿ and the Cheju dialect

All records of Middle Korean are exclusively in the Central dialect, the prestige form spoken in the capital, and all printed material in the newly-created Hangǔl script emanated from there. For this reason, historical studies must rely on modern dialect data for comparison and reconstruction, since there are virtually no early dialect materials. In this study, I investigate the nature of the MK ㅿ, which is most often realized as /Ø/ in Modern Standard Korean, but which often surfaces as /s/ in Southern varieties, including the most conservative of these dialects, Cheju Korean. Sino-Korean forms in Cheju dialect containing an /s/ reflex of ㅿ demonstrate not only that ㅿ was realized as /z/ in such forms, but also that the dialects must have had special phonological rules to deal with their pronunciation. A further important issue concerns the nature of doublets and their treatment in both Middle Korean and Cheju dialect.