The Collaborative International Dictionary of English v.0.48:

Muffle \Muf"fle\, v. t. [imp. & p. p. Muffled; p. pr. & vb. n.
   Muffling.] [Cf. F. moufle a mitten, LL. muffula, OD. moffel
   a muff. See Muff.]
   1. To wrap up in something that conceals or protects; to
      wrap, as the face and neck, in thick and disguising folds;
      hence, to conceal or cover the face of; to envelop; to
      inclose; -- often with up. --South.
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            The face lies muffled up within the garment.
                                                  --Addison.
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            He muffled with a cloud his mournful eyes. --Dryden.
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            Muffled up in darkness and superstition.
                                                  --Arbuthnot.
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   2. To prevent seeing, or hearing, or speaking, by wraps bound
      about the head; to blindfold; to deafen.
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   3. To wrap or fit with something that dulls or deadens the
      sound of; as, to muffle the strings of a drum, or that
      part of an oar which rests in the rowlock; to muffle the
      exhaust of a motor vehicle.
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