Source : Webster's Revised Unabridged Dictionary (1913)

Gloaming \Gloam"ing\, n. [See {Gloom}.]
   1. Twilight; dusk; the fall of the evening. [Scot. & North of
      Eng., and in poetry.] --Hogg.

   2. Sullenness; melancholy. [Obs.] --J. Still.

Source : WordNet®

gloaming
     n : the time of day immediately following sunset; "he loved the
         twilight"; "they finished before the fall of night" [syn:
          {twilight}, {dusk}, {nightfall}, {evenfall}, {fall}, {crepuscule},
          {crepuscle}]