[The Origins of the Words : Zenshin Masui and Kyokusho Masui.].

In 1850, Seikei Sugita coined the word "Masui" to describe a physical condition induced by ether inhala- tion. Therefore, the word"Masui"initially meant general anesthesia. After physical methods to produce local numbness were introduced to Japan, it was necessary to make a new phrase to express the methods and the physical condition produced by them, and "Kyokusho Masui" was made, in which "kyokusho" means local. Then,"Zenshin Masui", indicating general anesthesia, was made to form a set of "Kyokusho Masui" and "Zenshin Masui". It was 1876 when Tadanori Ishiguro published "Geka Tsujutsu", in which he described a clear definition of "Kyokusho Masui" and "Zenshin Masui". This is one of the earliest uses of "Kyokusho Masui" together with "Zenshin Masui" in Japan.