The Collaborative International Dictionary of English v.0.48:

Dim \Dim\, v. t. [imp. & p. p. Dimmed; p. pr. & vb. n.
   Dimming.]
   1. To render dim, obscure, or dark; to make less bright or
      distinct; to take away the luster of; to darken; to dull;
      to obscure; to eclipse.
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            A king among his courtiers, who dims all his
            attendants.                           --Dryden.
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            Now set the sun, and twilight dimmed the ways.
                                                  --Cowper.
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   2. To deprive of distinct vision; to hinder from seeing
      clearly, either by dazzling or clouding the eyes; to
      darken the senses or understanding of.
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            Her starry eyes were dimmed with streaming tears.
                                                  --C. Pitt.
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