Wikipedia
Ninjatō
The , , or , are allegedly the preferred weapon that the Shinobi of feudal Japan carried. It is portrayed by modern ninjutsu practitioners (including Masaaki Hatsumi and Stephen K. Hayes) and is prominently featured in popular culture. Replicas of this weapon are also prominently on display in both the Koka Ninja Village Museum in Kōka, Shiga and the Iga-ryū Ninja Museum in Iga, Mie. Historically, there is no physical evidence for the existence of this " katana-like short sword legendarily used by ninja", though it is believed that they are based on the design of the wakizashi or chokutō swords.