When looking at the meaning of “OSS” or “OSU”, it’s important to understand that the term has several uses ranging from a greeting to answering a question and acknowledging an opponent’s skill among other things.

OSS it’s a pretty generic term derived from Japanese martial arts. It is a particularly enthusiastic way of saying “yes” or to acknowledge something or someone, similar to the U.S. Marines when we say “OOH-RAH”.

The famous “OSS” has many origins. The first definition of “OSS” as an abbreviation for Onegai Shimasu, which translates into a request, a solicitation, an invitation like “please”, “if you may” or “with your permission”, much used when inviting a partner to train.

The second definition of the word, also known as “ossu”, means Oshi Shinobu, which conveys the idea of “persevering when pushed”. In other words, never give up, have determination, grit and withstand the most arduous of training.

Carrying on without giving up, under all kinds of pressure – that’s the idea of inner strength so common in Asian culture. Therefore, at the start of a fight, the martial artist will shout, invoke, emanate the “OSS”, as a way of letting this sentiment out.

In many sources, the term is defined as a manifestation of ki energy, or in other words, a different kiai (strength), indicating one is ready to fight. According to Miyamoto Musashi, in the book “Go rin no sho” (Book of the Five Rings), the samurai would use three types of shouts: one before combat, the second during combat, when attacking, to muster greater strength (kiai), and the third after the fight, to celebrate victory or bemoan defeat.

In BJJ, the term was made popular by Grand Master Carlson Gracie and was introduced as a sign of “respect”.