muf·fle / ˈməfəl/ • v. [tr.] (often be muffled) wrap or cover for warmth: on a chair by the far wall, muffled in an absurd overcoat. ∎ cover or wrap up (a source of sound) to reduce its loudness: [as adj.] (muffled) the soft beat of a muffled drum. ∎ make (a sound) quieter or less distinct: his voice was muffled. ∎ restrain or conceal (someone) with wrappings: the boy was bound and muffled.• n. [usu. as adj.] a receptacle in a furnace or kiln in which things can be heated without contact with combustion products.