The Collaborative International Dictionary of English v.0.48:

Hyphenated American \Hyphenated American\
   An American who is referred to by a hyphenated term with the
   first word indicating an origin in a foreign country, and the
   second term being "American", as Irish-American,
   Italian-American, African-American, Asian-American.
   Used in reference to Americans of foreign birth or ancestry.
   When used of Americans of European ancestry, it is often used
   to refer to those who have a strong attachment to the
   ancestral country or its culture. It implies that the
   individual is imperfectly assimilated into American culture,
   and is sometimes used derogatively.
   [Webster 1913 Suppl.]

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]

The Collaborative International Dictionary of English v.0.48:

African \Af"ri*can\, a. [L. Africus, Africanus, fr. Afer
   African.]
   Of or pertaining to Africa.
   [1913 Webster]

   African hemp, a fiber prepared from the leaves of the
      Sanseviera Guineensis, a plant found in Africa and
      India.

   African marigold, a tropical American plant (Tagetes
      erecta).

   African oak or African teak, a timber furnished by
      Oldfieldia Africana, used in ship building.
      [1913 Webster]

   African violet .

   African-American, see African-American.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

African-American \African-American\ adj.
   1. of or pertaining to or characteristic of Americans of
      African ancestry or their history or culture

   Syn: Afro-American
        [WordNet 1.5]

The Collaborative International Dictionary of English v.0.48:

African-American \African-American\ n.
   1. 1 an American whose ancestors were born in Africa,
      especially a United States citizen of African descent.

   Syn: Afro-American, African, black, negro
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

African-American
    adj 1: pertaining to or characteristic of Americans of African
           ancestry; "Afro-American culture"; "many black people
           preferred to be called African-American or Afro-American"
           [syn: African-American, Afro-American]
    n 1: an American whose ancestors were born in Africa [syn:
         African-American, African American, Afro-American,
         Black American]