Daishō

The daishō (大小, daishō^?)—literally "big-little"—is a Japanese term for a matched pair of traditionally made Japanese swords worn by the samurai class in feudal Japan.

The etymology of the word daishō becomes apparent when the terms daitō, meaning long sword, and shōtō, meaning short sword, are used; daitō + shōtō = daishō. A daishō is typically depicted as a katana and wakizashi mounted in matching but originally the daishō was the wearing of any long and short uchigatana together. The katana/wakizashi pairing is not the only daishō combination as generally any longer sword paired with a tantō is considered to be a daishō. Daishō eventually came to mean two swords having a . A daishō could also have matching blades made by the same swordsmith, but this was in fact uncommon and not necessary for two swords to be considered to be a daishō, as it would have been more expensive for a samurai.

The concept of the daisho originated with the pairing of a short sword with whatever long sword was being worn during a particular time period. It has been noted that the tachi would be paired with a tantō, and later the uchigatana would be paired with another shorter uchigatana. With the advent of the katana, the wakizashi eventually was chosen by samurai as the short sword over the tantō. Kanzan Satō, in his book titled The Japanese Sword, notes that there did not seem to be any particular need for the wakizashi and suggests that the wakizashi may have become more popular than the tantō as the wakizashi was more suited for indoor fighting. He mentions the custom of leaving the katana at the door of a castle or palace when entering while continuing to wear the wakizashi inside.

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