☆Hitokiri, literally meaning "Human Slayer", is a superlative name for this particular caliber of samurai.
☆Battōsai (抜刀斎) is a term used in the fictional universe of the manga and anime series Rurouni Kenshin. The name is romanized as Battōsai in the English manga and Battousai in the English anime.
Battōsai is the nickname for a particular swordsman, the protagonist in Rurouni Kenshin, who was skilled in battōjutsu (抜刀術, a technique that requires unsheathing the blade in one fluid motion). Battō (抜刀) literally means "sword drawing" and sai (斎) is a suffix added to pen names or professional working names.
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