Jonidan

Professional sumo is divided into six ranked divisions. Wrestlers are promoted and demoted within and between these divisions based on the merit of their win/loss records in official tournaments. For more information see kachi-koshi and make-koshi. Wrestlers are also ranked within each division. The higher a wrestler's rank within a division is, the stronger the general level of opponents he will have to face becomes. According to tradition, each rank is further subdivided into East and West, with East being slightly more prestigious, and ranked slightly higher than its West counterpart. The divisions, ranked in order of hierarchy from highest to lowest, are as follows:

Makuuchi (幕内), or makunouchi (幕の内), is the top division. It is fixed at 42 wrestlers who are ranked according to their ability, as defined by their performance in previous tournaments. At the top of the division are the "titleholders", or "champions" called the san'yaku comprising yokozuna, ōzeki, sekiwake and komusubi. There are typically 8–12 wrestlers in these ranks with the remainder, called maegashira, ranked in numerical order from 1 downwards. This is the only division that is featured on standard NHK's live coverage of sumo tournaments and is broadcast bilingually. The latter part of the lower divisions is shown on satellite coverage.

The name makuuchi literally means "inside the curtain", a reference to the early period of professional sumo, when the top ranked wrestlers were able to sit in a curtained off area prior to appearing for their bouts. Makuuchi can also refer to the top two divisions makuuchi and jūryō as a whole, as the wrestlers in these divisions are salaried and considered fully salaried professionals as opposed to "in training".

Jūryō (十両), is the second highest division, and is fixed at 28 wrestlers. The name literally means "ten ryō"', which was at one time the income a wrestler ranked in this division could expect to receive. The official name of the second division is actually jumaime (十枚目), meaning "tenth placing" and can be heard in official announcements and seen in some publications, but within and outside the sumo world it is almost universally known as jūryō. Wrestlers in the jūryō and the makuuchi division above are known as sekitori. Jūryō wrestlers, like those in the top makuuchi division, receive a regular monthly salary as well as other perks associated with having become a sekitori, or a member of the two upper divisions in sumo. Sumo wrestlers ranked in the divisions below jūryō are considered to be in training and receive a small allowance instead of a salary.

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