The true meaning and origins of the word "OSU" are finally revealed!

No matter where in the world you are, enter any karate dojo and the term most frequently heard is "OSU!" Karate's Universal Codeword is the first thorough examination of the origins and use of this word in the martial arts, and the fascinating story of how it has spread worldwide.

Its use has exploded far beyond karate into other martial arts like judo, aikido, Brazilian jiu-jitsu, kickboxing and mixed martial arts making it arguably the most frequently uttered Japanese word in the world. Yet ironically, very few martial artists (even in Japan) know the true origins and the deeper meaning behind the term. Although it is universally used, it remains a total mystery to everyone. This book promises to finally reveal the truth behind the word OSU and its fascinating origins.

『押忍とは何か？』（三五館刊）英訳版
空手をはるかに超え、世界中のあらゆる武道において使用されている”OSS”（オス）。本書はその「押忍」という普遍的なワードの源流と使い方、そしてそれが世界中や他の武道の分野に広まった経緯について、様々な諸説や各時代・シーンでの使い方を取りあげながら説明します。「押忍」に隠された謎と興味深い源流を徹底的に調べ上げて解説した、世界中の武道・格闘技ファン必読の一冊です。