A short katana is commonly referred to as a "wakizashi." The wakizashi is a traditional Japanese sword that is shorter in length compared to the standard katana. It typically has a blade length between 30 and 60 centimeters (12 to 24 inches), although exact measurements can vary.

The wakizashi was traditionally worn alongside the katana by samurai as a backup weapon or for indoor use where a longer sword would be impractical. It served as a symbol of a samurai's social status and was also utilized in close-quarter combat.

While the wakizashi is shorter than a katana, it shares similar design characteristics, including a curved, single-edged blade and a handle wrapped with traditional materials like tsuka-ito (cotton cord). It may also feature a tsuba (handguard) and other decorative elements.

The combination of the katana and wakizashi worn together is known as "daishō," which means "big and small" in Japanese. The daishō represented the social status and warrior identity of the samurai. The katana was the longer and primary weapon, while the wakizashi was the shorter companion sword.

It's important to note that the term "wakizashi" specifically refers to a short katana in the context of traditional Japanese swords. In other cultures or sword traditions, a shorter sword may have different names or classifications.