The Collaborative International Dictionary of English v.0.48:

Ghastly \Ghast"ly\, a. [Compar. Ghastlier; superl.
   Ghastliest.] [OE. gastlich, gastli, fearful, causing fear,
   fr. gasten to terrify, AS. g[ae]stan. Cf. Aghast, Gast,
   Gaze, Ghostly.]
   1. Like a ghost in appearance; deathlike; pale; pallid;
      dismal.
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            Each turned his face with a ghastly pang.
                                                  --Coleridge.
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            His face was so ghastly that it could scarcely be
            recognized.                           --Macaulay.
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   2. Horrible; shocking; dreadful; hideous.
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            Mangled with ghastly wounds through plate and mail.
                                                  --Milton.
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