The Collaborative International Dictionary of English v.0.48:

Flare \Flare\ (fl[^a]r), v. i. [imp. & p. p. Flared
   (fl[^a]rd); p. pr. & vb. n. Flaring.] [Cf. Norw. flara to
   blaze, flame, adorn with tinsel, dial. Sw. flasa upp, and E.
   flash, or flacker.]
   1. To burn with an unsteady or waving flame; as, the candle
      flares.
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   2. To shine out with a sudden and unsteady light; to emit a
      dazzling or painfully bright light.
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   3. To shine out with gaudy colors; to flaunt; to be
      offensively bright or showy.
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            With ribbons pendant, flaring about her head.
                                                  --Shak.
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   4. To be exposed to too much light. [Obs.]
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            Flaring in sunshine all the day.      --Prior.
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   5. To open or spread outwards; to project beyond the
      perpendicular; as, the sides of a bowl flare; the bows of
      a ship flare.
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   To flare up, to become suddenly heated or excited; to burst
      into a passion. [Colloq.] --Thackeray.
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The Collaborative International Dictionary of English v.0.48:

Flaring \Flar"ing\, a.
   1. That flares; flaming or blazing unsteadily; shining out
      with a dazzling light.
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            His [the sun's] flaring beams.        --Milton.
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   2. Opening or speading outwards.
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WordNet (r) 3.0 (2006):

flaring
    adj 1: streaming or flapping or spreading wide as if in a
           current of air; "ran quickly, her flaring coat behind
           her"; "flags aflare in the breeze" [syn: aflare,
           flaring]