The Collaborative International Dictionary of English v.0.48:

Shabby \Shab"by\, a. [Compar. Shabbier; superl. Shabbiest.]
   [See Shab, n., Scabby, and Scab.]
   1. Torn or worn to rage; poor; mean; ragged.
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            Wearing shabby coats and dirty shirts. --Macaulay.
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   2. Clothed with ragged, much worn, or soiled garments. "The
      dean was so shabby." --Swift.
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   3. Mean; paltry; despicable; as, shabby treatment. "Very
      shabby fellows." --Clarendon.
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