Source : Webster's Revised Unabridged Dictionary (1913)

Tympanites \Tym`pa*ni"tes\, n. [L., fr. Gr. ?, fr. ? a
   kettledrum.] (Med.)
   A flatulent distention of the belly; tympany.

Source : WordNet®

tympanites
     n : distension of the abdomen that is caused by the accumulation
         of gas in the intestines or the peritoneal cavity