noun one who muffles.
2. muffler ·noun a kind of mitten or boxing glove, ·esp. when stuffed.
3. muffler ·noun a cushion for terminating or softening a note made by a stringed instrument with a keyboard.
4. muffler ·noun anything used in muffling; ·esp., a scarf for protecting the head and neck in cold weather; a tippet.
5. muffler ·add. ·noun 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).