The Collaborative International Dictionary of English v.0.48:

Muzzle \Muz"zle\, v. t. [imp. & p. p. Muzzled; p. pr. & vb. n.
   Muzzling.] [F. museler.]
   1. To bind the mouth of; to fasten the mouth of, so as to
      prevent biting or eating; hence, figuratively, to bind; to
      sheathe; to restrain from speech or action; as, the
      dictator muzzled all the newspapers. "My dagger muzzled."
      --Shak.
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            Thou shalt not muzzle the ox when he treadeth out
            the corn.                             --Deut. xxv.
                                                  4.
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   2. To fondle with the closed mouth. [Obs.] --L'Estrange.
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