The Collaborative International Dictionary of English v.0.48:

Negro \Ne"gro\ (n[=e]"gr[-o]), n.; pl. Negroes
   (n[=e]"gr[=o]z). [Sp. or Pg. negro, fr. negro black, L.
   niger; perh. akin to E. night.]
   A black man; especially, one of a race of black or very dark
   persons who inhabit the greater part of tropical Africa, and
   are distinguished by crisped or curly hair, flat noses, and
   thick protruding lips; also, any black person of unmixed
   African blood, wherever found.
   [1913 Webster]

   2. A person of dark skin color descended at least in part
      from African negroes; in the United States, an
      African-American. [U.S. usage, sometimes considered
      offensive.]
      [PJC]