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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WordNet (r) 3.0 (2006):

evening grosbeak
    n 1: North American grosbeak [syn: evening grosbeak,
         Hesperiphona vespertina]