Source : Webster's Revised Unabridged Dictionary (1913)

Flatus \Fla"tus\, n.; pl. E. {Flatuses}, L. {Flatus}. [L., fr.
   flare to blow.]
   1. A breath; a puff of wind. --Clarke.

   2. Wind or gas generated in the stomach or other cavities of
      the body. --Quincy.