The Collaborative International Dictionary of English v.0.48:

Muddy \Mud"dy\, a. [Compar. Muddier; superl. Muddiest.]
   1. Abounding in mud; besmeared or dashed with mud; as, a
      muddy road or path; muddy boots.
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   2. Turbid with mud; as, muddy water.
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   3. Consisting of mud or earth; gross; impure.
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            This muddy vesture of decay.          --Shak.
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   4. Confused, as if turbid with mud; cloudy in mind; dull;
      stupid; also, immethodical; incoherent; vague.
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            Cold hearts and muddy understandings. --Burke.
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            Dost think I am so muddy, so unsettled. --Shak.
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   5. Not clear or bright. --Swift.
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