稽古着

The compound 'keikogi' joins 'keiko' (稽古, practice or training) and 'gi' (着, clothing or garment). 'Keiko' appears in Heian-period texts (794–1185) with the meaning of reflecting on ancient models: the character 稽 carries a sense of deliberation and care, not speed. The word applied to the study of classical arts, poetry, and court music long before it was attached to martial training. It named a quality of attention as much as a category of activity.

The garment took its modern form in 1882, when Jigoro Kano founded the Kodokan judo school in Tokyo. Kano designed a heavy cotton jacket and trousers whose seams could withstand the stress of randori, or free-practice throwing, without tearing. He called the uniform 'judogi' in formal contexts, but 'keikogi' was the everyday word for any training garment. The white two-piece design, jacket folded left-over-right and secured with a cloth belt, became the template for every martial arts uniform that followed.

As Japanese martial arts spread beyond their first schools, the keikogi traveled with them. Gichin Funakoshi brought karate from Okinawa to Tokyo in 1922, and his students wore white keikogi modeled closely on Kano's judo garment. Kendo practitioners adapted their own version, worn beneath lacquered armor from the Meiji era (1868–1912). Each discipline modified the weight and cut of the cloth while keeping the basic two-piece cotton structure intact.

American servicemen stationed in occupied Japan encountered judo and karate in Tokyo gymnasiums during the late 1940s and brought both disciplines to the United States. In American dojo speech, 'keiko' was dropped and 'gi' became the standard shorthand. That truncation has now settled so firmly that many English speakers do not recognize 'gi' as a shortened form of an older compound.