The Collaborative International Dictionary of English v.0.48:

Evening \E"ven*ing\, n. [AS. [=ae]fnung. See even, n., and cf.
   Eve.]
   1. The latter part and close of the day, and the beginning of
      darkness or night; properly, the decline of the day, or of
      the sun.
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            In the ascending scale
            Of heaven, the stars that usher evening rose.
                                                  --Milton.
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   Note: Sometimes, especially in the Southern parts of the
         United States, the afternoon is called evening.
         --Bartlett.
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   2. The latter portion, as of life; the declining period, as
      of strength or glory.
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   Note: Sometimes used adjectively; as, evening gun. "Evening
         Prayer." --Shak.
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   Evening flower (Bot.), a genus of iridaceous plants
      (Hesperantha) from the Cape of Good Hope, with
      sword-shaped leaves, and sweet-scented flowers which
      expand in the evening.

   Evening grosbeak (Zo["o]l.), an American singing bird
      (Coccothraustes vespertina) having a very large bill.
      Its color is olivaceous, with the crown, wings, and tail
      black, and the under tail coverts yellow. So called
      because it sings in the evening.

   Evening primrose. See under Primrose.

   The evening star, the bright star of early evening in the
      western sky, soon passing below the horizon; specifically,
      the planet Venus; -- called also Vesper and Hesperus.
      During portions of the year, Mars, Jupiter, and Saturn are
      also evening stars. See Morning Star.
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The Collaborative International Dictionary of English v.0.48:

Even \E"ven\, v. t. [imp. & p. p. Evened; p. pr. & vb. n.
   Evening]
   1. To make even or level; to level; to lay smooth.
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            His temple Xerxes evened with the soil. --Sir. W.
                                                  Raleigh.
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            It will even all inequalities         --Evelyn.
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   2. To equal. [Obs.] "To even him in valor." --Fuller.
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   3. To place in an equal state, as to obligation, or in a
      state in which nothing is due on either side; to balance,
      as accounts; to make quits; to make equal; as, to even the
      score. --Shak.
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   4. To set right; to complete.
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   5. To act up to; to keep pace with. --Shak.
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WordNet (r) 3.0 (2006):

evening
    n 1: 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,
         even, eventide]
    2: a later concluding time period; "it was the evening of the
       Roman Empire"
    3: the early part of night (from dinner until bedtime) spent in
       a special way; "an evening at the opera"

Moby Thesaurus II by Grady Ward, 1.0:

44 Moby Thesaurus words for "evening":
   accommodation, adjustment, afternoon, balancing, close of day,
   cockshut, coordination, crepuscular, dimpsy, dusk, duskiness,
   duskness, dusky, equalization, equalizing, equating, equation,
   equilibration, eve, even, evening up, evensong, eventide, gloaming,
   grayness, harmonization, integration, nightfall, party, reception,
   regularization, salon, setting sun, shut of day, soiree, sundown,
   sunset, sunsetty, symmetrization, the expiring day, twilight,
   twilighty, vesper, vespertine



Easton's 1897 Bible Dictionary:

Evening
   the period following sunset with which the Jewish day began
   (Gen. 1:5; Mark 13:35). The Hebrews reckoned two evenings of
   each day, as appears from Ex. 16:12: 30:8; 12:6 (marg.); Lev.
   23:5 (marg. R.V., "between the two evenings"). The "first
   evening" was that period when the sun was verging towards
   setting, and the "second evening" the moment of actual sunset.
   The word "evenings" in Jer. 5:6 should be "deserts" (marg.
   R.V.).