For the type of sword, see Katana. KATANA is a song performed by Roronoa Zoro for the One Piece Nippon Judan! 47 Cruise CD. Like the other songs in the album, it references a location in Japan, this location being the Fukushima Prefecture.
Katana - Wikipedia
Anime Characters Roronoa Katana 80cm / 31.5 Props Weapons Kozuki Toki Sword Toy Katana - AliExpress
One Piece: All of Zoro's Named Katanas Explained
Yoru, One Piece Wiki
Ipponmatsu, One Piece Wiki
The Cursed Holy Sword, One Piece Wiki
Kikoku Katana Sword of Trafalgar Law in Just $77 (Japanese Steel is al – HS Blades Enterprise
Katana - Wikipedia
Shimotsuki Ryuma, One Piece Wiki, Fandom
Sword, One Piece Wiki