noun (n)

• `Johnny' was applied as a nickname for Confederate soldiers by the Federal soldiers in the American Civil War; `greyback' derived from their grey Confederate uniforms(noun.person)

  Synonym:
  johnny, johnny reb, reb, rebel
  

  source: wordnet30
• a dowitcher with a grey back(noun.animal)

  Synonym:
  grayback, limnodromus griseus
  

  source: wordnet30
• a sandpiper that breeds in the Arctic and winters in the southern hemisphere(noun.animal)

  Synonym:
  calidris canutus, grayback, knot
  

  source: wordnet30