nightfall

from WordNet (r) 3.0 (2006)

nightfall
    n 1: the time of day immediately following sunset; "he loved the
         twilight"; "they finished before the fall of night" [syn:
         {twilight}, {dusk}, {gloaming}, {gloam}, {nightfall},
         {evenfall}, {fall}, {crepuscule}, {crepuscle}]

from The Collaborative International Dictionary of English v.0.48

Nightfall \Night"fall`\, n.
   The close of the day; the arrival of the night; the period at
   and just after dusk. --Swift.
   [1913 Webster +PJC]

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