The Collaborative International Dictionary of English v.0.48:

Gloom \Gloom\, v. i. [imp. & p. p. Gloomed; p. pr. & vb. n.
   Glooming.]
   1. To shine or appear obscurely or imperfectly; to glimmer.
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   2. To become dark or dim; to be or appear dismal, gloomy, or
      sad; to come to the evening twilight.
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            The black gibbet glooms beside the way. --Goldsmith.
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            [This weary day] . . . at last I see it gloom.
                                                  --Spenser.
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The Collaborative International Dictionary of English v.0.48:

Glooming \Gloom"ing\, n. [Cf. Gloaming.]
   Twilight (of morning or evening); the gloaming.
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         When the faint glooming in the sky
         First lightened into day.                --Trench.
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         The balmy glooming, crescent-lit.        --Tennyson.
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WordNet (r) 3.0 (2006):

glooming
    adj 1: depressingly dark; "the gloomy forest"; "the glooming
           interior of an old inn"; "`gloomful' is archaic" [syn:
           glooming, gloomy, gloomful, sulky]