blacksnake

from WordNet (r) 3.0 (2006)

blacksnake
    n 1: large harmless shiny black North American snake [syn:
         {black rat snake}, {blacksnake}, {pilot blacksnake},
         {mountain blacksnake}, {Elaphe obsoleta}]
    2: blackish racer of the eastern United States that grows to six
       feet [syn: {blacksnake}, {black racer}, {Coluber
       constrictor}]

from The Collaborative International Dictionary of English v.0.48

Black snake \Black" snake`\ (sn[=a]k) or Blacksnake
\Black"snake\, n. (Zool.)
   A snake of a black color, of which two species are common in
   the United States, the {Bascanium constrictor}, or racer,
   sometimes six feet long, and the {Scotophis Alleghaniensis},
   seven or eight feet long.
   [1913 Webster]

   Note: The name is also applied to various other black
         serpents, as {Natrix atra} of Jamaica.
         [1913 Webster]