Source : Webster's Revised Unabridged Dictionary (1913)

Bleb \Bleb\, n. [Prov. E. bleb, bleib, blob, bubble, blister.
   This word belongs to the root of blub, blubber, blabber, and
   perh. blow to puff.]
   A large vesicle or bulla, usually containing a serous fluid;
   a blister; a bubble, as in water, glass, etc.

         Arsenic abounds with air blebs.          --Kirwan.

Source : WordNet®

bleb
     n : (pathology) an elevation of the skin filled with serous
         fluid [syn: {blister}, {bulla}]