Mutter \Mut"ter\, v. i. [imp. & p. p. Muttered; p. pr. & vb.
   n. Muttering.] [Prob. of imitative origin; cf. L. muttire,
   mutire.]
   1. To utter words indistinctly or with a low voice and lips
      partly closed; esp., to utter indistinct complaints or
      angry expressions; to grumble; to growl.
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            Wizards that peep, and that mutter.   --Is. viii.
                                                  19.
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            Meantime your filthy foreigner will stare,
            And mutter to himself.                --Dryden.
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   2. To sound with a low, rumbling noise.
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            Thick lightnings flash, the muttering thunder rolls.
                                                  --Pope.
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