The Collaborative International Dictionary of English v.0.48:

Belch \Belch\ (b[e^]lch; 224), v. t. [imp. & p. p. Belched
   (b[e^]lch); p. pr. & vb. n. Belching.] [OE. belken, AS.
   bealcan, akin to E. bellow. See Bellow, v. i.]
   1. To eject or throw up from the stomach with violence; to
      eruct.
      [1913 Webster]

            I belched a hurricane of wind.        --Swift.
      [1913 Webster]

   2. To eject violently from within; to cast forth; to emit; to
      give vent to; to vent.
      [1913 Webster]

            Within the gates that now
            Stood open wide, belching outrageous flame.
                                                  --Milton.
      [1913 Webster]

WordNet (r) 3.0 (2006):

belching
    n 1: the forceful expulsion of something from inside; "the
         belching of smoke from factory chimneys"
    2: a reflex that expels gas noisily from the stomach through the
       mouth [syn: belch, belching, burp, burping,
       eructation]