Shuriken 手里剑
A shuriken (Japanese 手裏剣; literally: "sword hidden in user's hand") is a traditional Japanese concealed weapon that was generally used for throwing, and sometimes stabbing or slashing. They are sharpened hand-held blades made from a variety of everyday items, such as needles, nails and knives, as well as coins, washers, and other flat plates of metal. Shuriken is the name given to any small-bladed object, while shaken is traditionally used to indicate the well-known "throwing star".