The expression OSS was created in the Japanese Naval School and is universally used for everyday expressions such as please, thank you, I understand, sorry, greeting someone, etc., as well as inside the world of karate nearly any time a response is required. You must say it from your abdomen.

This is not really used in Wado Karate or Budo arts, I remember been away at a WKF World Championship and every second karate-ka you passes would say or go oss. Some of the members of our team were from the Ed Parkers Kempo and found it funny to go OSS and get an answer back of, yes you guessed it OSS.