Muffler

n.
  1. Anything used in muffling; esp., a scarf for protecting the head and neck in cold weather; a tippet.
  2. (Mus.) A cushion for terminating or softening a note made by a stringed instrument with a keyboard.
  3. A kind of mitten or boxing glove, esp. when stuffed.
  4. One who muffles.
  5. (Mach.) Any of various devices to deaden the noise of escaping gases or vapors, as a tube filled with obstructions, through which the exhaust gases of an internal-combustion engine, as on an automobile, are passed (called also silencer).