The Collaborative International Dictionary of English v.0.48:

Flourish \Flour"ish\, v. i. [imp. & p. p. Flourished; p. pr. &
   vb. n. Flourishing.] [OE. florisshen, flurisshen, OF.
   flurir, F. fleurir, fr. L. florere to bloom, fr. flos,
   floris, flower. See Flower, and -ish.]
   1. To grow luxuriantly; to increase and enlarge, as a healthy
      growing plant; a thrive.
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            A tree thrives and flourishes in a kindly . . .
            soil.                                 --Bp. Horne.
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   2. To be prosperous; to increase in wealth, honor, comfort,
      happiness, or whatever is desirable; to thrive; to be
      prominent and influental; specifically, of authors,
      painters, etc., to be in a state of activity or
      production.
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            When all the workers of iniquity do flourish. --Ps.
                                                  xcii 7
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            Bad men as frequently prosper and flourish, and that
            by the means of their wickedness.     --Nelson.
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            We say
            Of those that held their heads above the crowd,
            They flourished then or then.         --Tennyson.
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   3. To use florid language; to indulge in rhetorical figures
      and lofty expressions; to be flowery.
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            They dilate . . . and flourish long on little
            incidents.                            --J. Watts.
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   4. To make bold and sweeping, fanciful, or wanton movements,
      by way of ornament, parade, bravado, etc.; to play with
      fantastic and irregular motion.
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            Impetuous spread
            The stream, and smoking flourished o'er his head.
                                                  --Pope.
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   5. To make ornamental strokes with the pen; to write
      graceful, decorative figures.
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   6. To execute an irregular or fanciful strain of music, by
      way of ornament or prelude.
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            Why do the emperor's trumpets flourish thus? --Shak.
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   7. To boast; to vaunt; to brag. --Pope.
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WordNet (r) 3.0 (2006):

flourishing
    adj 1: very lively and profitable; "flourishing businesses"; "a
           palmy time for stockbrokers"; "a prosperous new
           business"; "doing a roaring trade"; "a thriving tourist
           center"; "did a thriving business in orchids" [syn:
           booming, flourishing, palmy, prospering,
           prosperous, roaring, thriving]