What Does OSS Mean In BJJ?

What does OSS mean?

If you do any Jiu Jitsu training for any amount of time, then you are likely to have heard “OSS.” The phrase OSS is used by every single person that practices Brazilian Jiu Jitsu.

When you go to BJJ class, you are 100% likely to hear everyone there say OSS at least once. But what does the phrase OSS really mean and where does it come from?

Let’s dig into this BJJ phrase and see where the term OSS originated from. Going over possible origins of the term OSS and how it is used in BJJ training today.

Who started using “OSS” in BJJ?

The person that started using the term OSS in BJJ was the martial arts founder Grandmaster Carlos Gracie Sr. Carlos Sr didn’t come up with the term, but adopted it from somewhere within Japanese culture (Likely martial arts based).

He wanted a term that would connect terms of Jiu Jitsu together to show each other respect. Whenever one BJJ student would see the other, they would say OSS and then say it again one they parted.

What are the origins of “OSS?”

Obviously, Carlos Gracie Sr took the term OSS from somewhere within Japanese culture. There have been a few different origin theories for the term OSS that have been proposed over the years. Here are some of the most possible origins for the term OSS detailed below.

The good morning theory 

A language expert from Japan named Dr. Mizutani Osamu has an interesting theory about where the term OSS. Dr. Osamu believes that OSS is a contraction of the phrase “ohayo gozaimasu.”

This phrase is often used in Japanese as hey or good morning. Many have shortened the phrase and just say OSS.

Japanese Naval Academy 

Another strong theory for the origins of OSS may have come from a phrase said in the Japanese Naval Academy. Cadets and commanding officers from the academy use the phrase “onegai shimassu.”

The phrase is used between members of the academy once their conversation ends and they part ways. When you say this phrase it is a way of hoping for future interactions with this person.

The please theory

OSS could also could have been taken from the Japanese phrase “onegaishimasu.” A phrase that means please take care of me or please have patience with me. This is known as the please theory.

Kyokushin Karate 

The place that Carlos Gracie Sr most likely got the term OSS from is from Kyokushin Karate. In Kyokushin Karate, they use the term osu no seishin or OSU for short.

This term has a variety of different meanings from: to show combat spirit, give effort, overcome obstacles, going forward with a positive attitude, or show the spirit of perseverance. 

These definitions are why Carlos Gracie Sr likely adopted the term OSS into Jiu Jitsu.

The meaning of “OSS?”

The term OSS doesn’t just have one meaning, but multiple meanings in BJJ. This was Carlos Gracie Sr’s intent when he started using OSS in Jiu Jitsu classes.

OSS specifically has three meanings that includes:

  • Respect
  • Acknowledgment
  • Encouragement


First and foremost, the term OSS is a sign of respect between those that practice the martial art. Everyone that trains together in Jiu Jitsu is supposed to show each other the utmost respect.

By saying OSS to your instructor or teammate, you are showing that you respect them. After you say OSS to them, they will show the same respect to you and say OSS.


The second meaning for the term OSS is a way of acknowledging someone. A way of either acknowledging that you understand something that is being explained.

A good example of this is when an instructor is explaining the steps of a technique that you’re having trouble with. After they give an explanation, they’ll ask if you understood and you can give acknowledgement by saying OSS.


OSS is also used as a form of encouragement. For example, a teammate is feeling really nervous about a competition and is having anxiety about it. 

By saying something to encourage and end it by saying OSS, this can give them encouragement. They will be less stressed knowing that you’re there with them and you have their back.

How to use OSS in a sentence

If you’re new to BJJ and just hearing the word OSS, you may not be sure how to use it in a sentence. Here are a few different ways that OSS can be used in sentences.

How is OSS used in conversation?

There are three different ways that OSS can be used in a conversation. Here are the three scenarios detailed below.

Intro to BJJ class

Of course the most obvious way OSS is used in a conversation is the intro to a Jiu Jitsu class. At the beginning of class the instructor will bow the class in, say OSS. The class will respond with OSS as they bow back to the instructor which signifies the start of class.

Hello and goodbye

OSS is sort of like the Jiu Jitsu version of the hebrew word shalom. It can both mean hello and goodbye.

When you start a conversation with someone you can say OSS or if when it’s over you can also say OSS.

The begining or end of a roll

Much like the hello and goodbye scenario, OSS is also used at the beginning or end of a roll. You can say OSS as you slap, bump, and roll, or after the roll is finished.

Using OSS too much? 

Honestly, the overuse of the word OSS has sort of become an inside joke in the BJJ community. You’ve probably laughed at different memes making jokes over this topic.

There are always new people in Jiu Jitsu schools that become newly obsessed with Jiu Jitsu. Some of these new BJJ students will use the term OSS ad nauseum. Even using the term OSS when speaking to people that don’t train and look like a crazy person.

If you are this person, then yes. You need to settle down with using the word OSS and only use it with other Jiu Jitsu people.

Last thoughts on OSS

No matter how you feel about the term OSS or where you think it came from, there is one thing certain. The term OSS is a term that is designed to bring those that train Jiu Jitsu together.

Those that train together have a special bond and one of the ways they acknowledge their connection is by using OSS. So just know if someone you train with says OSS to you, they’re showing the utmost respect to you. As a teammate and as a friend.