early 15c., "to cover or wrap (something) to conceal or protect," perhaps from Old French moufle "thick glove, mitten;" see muff (n.). Compare Old French enmoufle "wrapped up;" Middle French mofler "to stuff." The meaning "wrap something up to deaden sound" is recorded by 1761. Related: Muffled; muffling. Muffled oars have mats or canvas about their shafts to prevent noise from contact with the oarlocks while rowing.