[1] : The Collaborative International Dictionary of English v.0.48

butterball \but"terball`\, n. zool.
   1. the buffel duck.
      1913 webster

   2. a fat person or animal. informal
      pjc

   3. a lump of butter rounded into a ball.
      pjc

   4. trademark a plump chicken or turkey prepared for
      cooking.
      pjc

[2] : WordNet (r) 2.0

butterball
     n 1: a rotund individual syn: fatso, fatty, fat person, roly-poly
          ant: thin person
     2: small north american diving duck; males have bushy head
        plumage syn: bufflehead, dipper, bucephela albeola
see also:
fatso fatty fat person roly-poly thin person bufflehead 
dipper bucephela albeola 

Butterball >> B Words
Butterball, definition of term: Butterball
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