S-rank (Earth-2356)

S-rank is one of the six general classifications around the galaxy. It is preceded by A-rank. Within the Jedi Order, it was typically used when classifying techniques intended for highly experienced Jedi Masters, Jedi High Masters and Master of the Order-level Jedi. S-rank techniques are almost always unique to a single user, and as such are trademark abilities of that user.

Missions and bounties can also be classified as S-rank, these are the highest paying and most dangerous type of bounties a bounty hunter can go after, as well as highly dangerous military or Jedi missions. These missions are exclusively assigned to highly skilled and reliable bounty hunters or, in the case of the Jedi, skilled Masters. S-rank missions pay at least 1,000,000 credits.

S-rank was also a designation given to extremely powerful rogue Jedi, earning them a place in the bingo book. The organization Akatsuki was comprised exclusively of S-rank rogue Jedi.

Source

 * https://naruto.fandom.com/wiki/S-rank