The Collaborative International Dictionary of English v.0.48:

Blossom \Blos"som\ (bl[o^]s"s[u^]m), n. [OE. blosme, blostme,
   AS. bl[=o]sma, bl[=o]stma, blossom; akin to D. bloesem, L.
   fios, and E. flower; from the root of E. blow to blossom. See
   Blow to blossom, and cf. Bloom a blossom.]
   1. The flower of a plant, or the essential organs of
      reproduction, with their appendages; florescence; bloom;
      the flowers of a plant, collectively; as, the blossoms and
      fruit of a tree; an apple tree in blossom.
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   Note: The term has been applied by some botanists, and is
         also applied in common usage, to the corolla. It is
         more commonly used than flower or bloom, when we have
         reference to the fruit which is to succeed. Thus we use
         flowers when we speak of plants cultivated for
         ornament, and bloom in a more general sense, as of
         flowers in general, or in reference to the beauty of
         flowers.
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               Blossoms flaunting in the eye of day.
                                                  --Longfellow.
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   2. A blooming period or stage of development; something
      lovely that gives rich promise.
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            In the blossom of my youth.           --Massinger.
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   3. The color of a horse that has white hairs intermixed with
      sorrel and bay hairs; -- otherwise called peach color.
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   In blossom, having the blossoms open; in bloom.
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