The Collaborative International Dictionary of English v.0.48:

Flame \Flame\ (fl[=a]m), n. [OE. flame, flaume, flaumbe, OF.
   flame, flambe, F. flamme, fr. L. flamma, fr. flamma, fr.
   flagrare to burn. See Flagrant, and cf. Flamneau,
   Flamingo.]
   1. A stream of burning vapor or gas, emitting light and heat;
      darting or streaming fire; a blaze; a fire.
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   2. Burning zeal or passion; elevated and noble enthusiasm;
      glowing imagination; passionate excitement or anger. "In a
      flame of zeal severe." --Milton.
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            Where flames refin'd in breasts seraphic glow.
                                                  --Pope.
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            Smit with the love of sister arts we came,
            And met congenial, mingling flame with flame.
                                                  --Pope.
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   3. Ardor of affection; the passion of love. --Coleridge.
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   4. A person beloved; a sweetheart. --Thackeray.

   Syn: Blaze; brightness; ardor. See Blaze.
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   Flame bridge, a bridge wall. See Bridge, n., 5.

   Flame color, brilliant orange or yellow. --B. Jonson.

   Flame engine, an early name for the gas engine.

   Flame manometer, an instrument, invented by Koenig, to
      obtain graphic representation of the action of the human
      vocal organs. See Manometer.

   Flame reaction (Chem.), a method of testing for the
      presence of certain elements by the characteristic color
      imparted to a flame; as, sodium colors a flame yellow,
      potassium violet, lithium crimson, boracic acid green,
      etc. Cf. Spectrum analysis, under Spectrum.

   Flame tree (Bot.), a tree with showy scarlet flowers, as
      the Rhododendron arboreum in India, and the
      Brachychiton acerifolium of Australia.
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WordNet (r) 3.0 (2006):

flame tree
    n 1: a terrestrial evergreen shrub or small tree of western
         Australia having brilliant yellow-orange flowers; parasitic
         on roots of grasses [syn: flame tree, fire tree,
         Christmas tree, Nuytsia floribunda]
    2: showy tropical tree or shrub native to Madagascar; widely
       planted in tropical regions for its immense racemes of
       scarlet and orange flowers; sometimes placed in genus
       Poinciana [syn: royal poinciana, flamboyant, flame
       tree, peacock flower, Delonix regia, Poinciana regia]
    3: north Australian tree having white flowers and broad leaves
       [syn: flame tree, broad-leaved bottletree, Brachychiton
       australis]
    4: south Australian tree having panicles of brilliant scarlet
       flowers [syn: flame tree, flame durrajong, Brachychiton
       acerifolius, Sterculia acerifolia]
    5: tropical American thorny shrub or small tree; fragrant yellow
       flowers used in making perfumery [syn: huisache, cassie,
       mimosa bush, sweet wattle, sweet acacia, scented
       wattle, flame tree, Acacia farnesiana]