The Collaborative International Dictionary of English v.0.48:

Flowering \Flow"er*ing\, n.
   1. The act of blossoming, or the season when plants blossom;
      florification.
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   2. The act of adorning with flowers.
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The Collaborative International Dictionary of English v.0.48:

Flower \Flow"er\ (flou"[~e]r), v. i. [imp. & p. p. Flowered
   (flou"[~e]rd); p. pr. & vb. n. Flowering.] [From the noun.
   Cf. Flourish.]
   1. To blossom; to bloom; to expand the petals, as a plant; to
      produce flowers; as, this plant flowers in June.
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   2. To come into the finest or fairest condition.
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            Their lusty and flowering age.        --Robynson
                                                  (More's
                                                  Utopia).
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            When flowered my youthful spring.     --Spenser.
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   3. To froth; to ferment gently, as new beer.
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            That beer did flower a little.        --Bacon.
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   4. To come off as flowers by sublimation. [Obs.]
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            Observations which have flowered off. --Milton.
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The Collaborative International Dictionary of English v.0.48:

Flowering \Flow"er*ing\, a. (Bot.)
   Having conspicuous flowers; -- used as an epithet with many
   names of plants; as, flowering ash; flowering dogwood;
   flowering almond, etc.
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   Flowering fern, a genus of showy ferns (Osmunda), with
      conspicuous bivalvular sporangia. They usually grow in wet
      places.

   Flowering plants, plants which have stamens and pistils,
      and produce true seeds; phenogamous plants; --
      distinguished from flowerless plants.

   Flowering rush, a European rushlike plant (Butomus
      umbellatus), with an umbel of rosy blossoms.
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WordNet (r) 3.0 (2006):

flowering
    adj 1: having a flower or bloom; "a flowering plant" [ant:
           flowerless, nonflowering]
    n 1: the time and process of budding and unfolding of blossoms
         [syn: blossoming, flowering, florescence,
         inflorescence, anthesis, efflorescence]
    2: a developmental process; "the flowering of antebellum
       culture" [syn: unfolding, flowering]