OSS it's a pretty generic term derived from Japanese martial arts. It is a particularly enthusiastic way of saying âyesâ or to acknowledge something or someone, similar to the U.S. Marines when we say âOOH-RAHâ.
The famous âOSSâ has many origins. The first definition of âOSSâ as an abbreviation for Onegai Shimasu, which translates into a request, a solicitation, an invitation like âpleaseâ, âif you mayâ or âwith your permissionâ, much used when inviting a partner to train.
Sensei: Are you ready?
Kouhais: OSS!