The Collaborative International Dictionary of English v.0.48:
Tympanites \Tym`pa*ni"tes\, n. [L., fr. Gr. tympani`ths, fr. ty`mpanon a kettledrum.] (Med.) A flatulent distention of the belly; tympany. [1913 Webster]WordNet (r) 3.0 (2006):
tympanites n 1: distension of the abdomen that is caused by the accumulation of gas in the intestines or the peritoneal cavity