The Collaborative International Dictionary of English v.0.48:

Sickly \Sick"ly\, a. [Compar. Sicklier; superl. Sickliest.]
   1. Somewhat sick; disposed to illness; attended with disease;
      as, a sickly body.
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            This physic but prolongs thy sickly days. --Shak.
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   2. Producing, or tending to, disease; as, a sickly autumn; a
      sickly climate. --Cowper.
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   3. Appearing as if sick; weak; languid; pale.
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            The moon grows sickly at the sight of day. --Dryden.
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            Nor torrid summer's sickly smile.     --Keble.
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   4. Tending to produce nausea; sickening; as, a sickly smell;
      sickly sentimentality.
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   Syn: Diseased; ailing; infirm; weakly; unhealthy; healthless;
        weak; feeble; languid; faint.
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