Source : Webster's Revised Unabridged Dictionary (1913)

Eventide \E"ven*tide`\n. [AS. [=ae]fent[=i]d. See {Tide}.]
   The time of evening; evening. [Poetic.] --Spenser.

Source : WordNet®

eventide
     n : the latter part of the day (the period of decreasing
         daylight from late afternoon until nightfall); "he
         enjoyed the evening light across the lake" [syn: {evening},
          {eve}]