Shikona

A shikona (Japanese: 四股名 or 醜名) is a sumo wrestler's stage name.As with standard Japanese names, a shikona consists of a 'surname' and a 'given' name, and the full name is written surname first. However, the given name is rarely used outside formal or ceremonial occasions. Thus, the current yokozuna Asashōryū Akinori is usually referred to as simply Asashōryū. When addressing a sumo wrestler or the makuuchi or jūryō divisions, the suffix -zeki (関) should be used instead of the usual Japanese -san. The given name is often the wrestler's actual name, although foreign wrestlers are invariably given a Japanese name.
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The wrestlers' fighting name- much like an actor's stage name. A wrestler usually starts out using his own name, and as he climbs up the rankings, he uses a "ring-name". A fraction of high-ranking wrestlers maintain their real names (Dejima).