Sino-Kijapani cha Okinawa

This is NOT Okinawan proper (Uchinaaguchi 沖縄口, a separate Ryukyuan language with its own Sino-Ryukyuan readings); it is the variety of MODERN JAPANESE spoken in Okinawa with substrate influence from Okinawan phonology — sometimes called Uchinaa-yamatuguchi (ウチナーヤマトゥグチ, 'Okinawan-flavoured Japanese'). The single most pervasive substrate effect on Sino-Japanese citation forms is the canonical Ryukyuan three-vowel raising: short /e/ → /i/, short /o/ → /u/, long /eː/ → /iː/, long /oː/ → /uː/. Thus 月 getsu → gitsu, 東 tō → tū, 西 sei → sii, 見 ken → kin, 木 boku → buku, 五 go → gu. Diphthongs /ai au/ are typically preserved (海 kai, 来 rai). This raising affects every vowel in the inventory and so reshapes a large fraction of common on-yomi, making it the most systematic Sino-Japanese reading difference of any Japanese dialect. Data here follow the substrate phonology described by Shimoji (2010) for Okinawan and Pellard for Ryukyuan, applied to standard Hepburn citation forms.