shuriken; throwing star; small throwing blade
A traditional Japanese concealed weapon, often star-shaped or spike-shaped, used by ninja.
The ninja threw a shuriken and defeated the enemy.
I saw a real shuriken at the museum.
From 手裏 (shuri, 'in the hand') + 剣 (ken, 'blade'). The exact historical derivation is uncertain, but the term refers to a blade concealed in the hand.