The Collaborative International Dictionary of English v.0.48:

Flatulent \Flat"u*lent\, a. [L. flatus a blowing, flatus ventris
   windiness, flatulence, fr. flare to blow: cf. F. flatulent.
   See Blow.]
   1. Affected with flatus[2] or gases generated in the
      alimentary canal; windy.
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   2. Generating, or tending to generate, wind in the stomach.
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            Vegetables abound more with a["e]rial particles than
            animal substances, and therefore are more flatulent.
                                                  --Arbuthnot.
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   3. Turgid with flatus; as, a flatulent tumor. --Quincy.
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   4. Pretentious without substance or reality; puffy; empty;
      vain; as, a flatulent vanity.
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            He is too flatulent sometimes, and sometimes too
            dry.                                  --Dryden.
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WordNet (r) 3.0 (2006):

flatulent
    adj 1: generating excessive gas in the alimentary canal
    2: suffering from excessive gas in the alimentary canal [syn:
       colicky, flatulent, gassy]