If you’ve been around Gracie Jiu Jitsu for a while you have probably heard people saying ‘OSS’ during class. Though widely used, few know the terms actual meaning and history.

‘Oss’ is a term used in many Brazilian Jiu Jitsu schools as well as in other martial art styles. The origins of ‘Oss’ or ‘Osu’ (pronounced ‘ohss’) are not known exactly but there are two possible meaning. It is derived from the Japanese term ‘Onegai Shimasu’ which is a polite invitation like “Please, if you will”, or ‘Oshi Shinobu’ which roughly means “persevering when pushed” or “enduring under pressure”; values that are very much in line with the tradition of the Asian martial arts. Though it comes from Japanese phrases and most likely originated in Okinawa, it is not actually a Japanese word used by everyday speakers.

Oss was originally used exclusively in the martial arts to invite a training partner to practice, yelled to invoke one’s ki (‘vital energy’ or ‘spirit’) before an attack or combat (just as the samurai use to shout out). Or lastly, and still most commonly in Karate, to respond in the affirmative to a master’s or instructor’s directive and comments.

In Brazilian Jiu Jitsu these days you will mostly find it used at the end of a class as everyone bows out together, sometimes to recognize a partner or person’s efforts, or simply as a formal ‘yes’.