peashooter

noun

1. A toy weapon consisting of a tube through which dried peas or small objects are blown.
2. A person who uses such a device.
3. (slang)Any small or ineffective gun or weapon.

   “Compared to my forty-five, it's a toy. Christ, Thanet, why did you buy it in the first place? I would have given you one of mine, a real weapon, one with knock down power, compared to that peashooter on your hip.”