Source : Webster's Revised Unabridged Dictionary (1913)

Gob \Gob\ (g[o^]b), n. [Cf. {Goaf}.] (Mining)
   Same as {Goaf}.

Gob \Gob\, n. [OF. gob morsel; cf. F. gobe, gobbe, a poisoned
   morsel, poison ball, gobet a piece swallowed, gober to
   swallow greedily and without tasting; cf. Gael. & Ir. gob
   mouth, snout, W. gwp a bird's head and neck. Cf. {Gobble},
   {Job}, n.]
   1. A little mass or collection; a small quantity; a mouthful.
      [Low] --L'Estrange.

   2. The mouth. [Prov. Eng.or Low] --Wright.

Source : WordNet®

gob
     n 1: a man who serves as a sailor [syn: {mariner}, {seaman}, {tar},
           {Jack-tar}, {Jack}, {old salt}, {seafarer}, {sea dog}]
     2: a lump of slimey stuff; "a gob of phlegm"
     3: informal terms for the mouth [syn: {trap}, {cakehole}, {hole},
         {maw}, {yap}]