c.1430, "to cover or wrap (something) to conceal or protect," perhaps from M.Fr. mofler "to stuff," from O.Fr. moufle "thick glove, muff" (cf. O.Fr. enmoufle "wrapped up"); see muff (n.). Meaning "wrap something up to deaden sound" first recorded 1761. Muffler as a kind of scarf is from 1535; as an automobile exhaust system silencer, it is attested from 1895.