nighttime

from WordNet (r) 3.0 (2006)

nighttime
    n 1: the time after sunset and before sunrise while it is dark
         outside [syn: {night}, {nighttime}, {dark}] [ant: {day},
         {daylight}, {daytime}]

from The Collaborative International Dictionary of English v.0.48

Nighttime \Night"time`\, n.
   The time from dusk to dawn; -- opposed to {daytime}.
   [1913 Webster]

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