ぐすく

Unclear. The initial gu may be cognate with 御 (go, “honorific”), but it is problematic in that the only honorary prefixes found in Omoro Sōshi are 御 (mi) and 御 (o). Suku may be related to しけ (shike, “a holy place”) or cognate with 塞 (soko, “fortress”). While written with the kanji for "castle", textual and cultural evidence suggests that the initial primary meaning was a holy place.

ぐすく • (gusuku) 

1. a place of worship
2. 城: castle
   • 1531-1623: Omoro Sōshi

     一 聞得大君ぎや 降れて 遊びよわれば 天が下 平らげて ちよわれ 又 鳴響む精高子が 又 首里杜ぐすく 真玉杜ぐすく

• Hokama, Shuzen; Nobutsuna Saigō (1972) Nihon Shisō Taikai 18: Omoro Sōshi (in Japanese), Tōkyō: Iwanami Shoten