Source : Webster's Revised Unabridged Dictionary (1913)

Abb \Abb\ ([a^]b), n. [AS. [=a]web, [=a]b; pref. a- + web. See
   {Web}.]
   Among weavers, yarn for the warp. Hence, {abb wool} is wool
   for the abb.

Source : WordNet®

ABB
     n : an urban hit squad and guerrila group of the Communist Party
         in the Philippines; formed in the 1980s [syn: {Alex
         Boncayao Brigade}, {Revolutionary Proletarian Army}, {RPA-ABB}]