noun (n)

• a larval frog or toad(noun.animal)

  Synonym:
  polliwog, pollywog
  

  source: wordnet30
• The young aquatic larva of any amphibian. In this stage it breathes by means of external or internal gills, is at first destitute of legs, and has a finlike tail. Called also polliwig, polliwog, porwiggle, or purwiggy.(noun)

  source: webster1913