A tantō (短刀, "short blade"), commonly referred as a knife or dagger is one of the traditionally made Japanese swords (nihonto) that were worn by the samurai class of feudal Japan. The tantō dates to the Heian period, when it was mainly used as a weapon but evolved in design over the years to become more ornate. Tantō were used in traditional martial arts (tantojutsu) and saw a resurgence of use in the West in the 1980s as the design made its way to America and is a common blade pattern found in modern tactical knives.
The tantō was designed primarily as a stabbing weapon, but the edge can be used for slashing as well.
In Gameplay Edit
It is the main weapon of Kaede and San the Rose Balsam. Its dual purpose as a stabbing and slashing weapon is seen in gameplay: In combat it's used in combination with Kaede's taijutsu as a slashing weapon, while it's exclusively used as a stabbing weapon during stealth kills.
Unusually for the typical weapon design, Kaede's and San's tantō has a diagonal handle. This may be to facilitate holding the weapon in a reverse grip, as both kunoichi seem to exclusively do.