The Collaborative International Dictionary of English v.0.48:

apartheid \apartheid\ n. [Afrikaans, fr. D. apart apart + -heid
   -hood.]
   1. segregation by race; -- a term used in South Africa.

   Syn: racial segregation
        [WordNet 1.5]

   2. the official policy of strict segregation by race
      practised by the government of the Union of South Africa
      up to 1993.
      [WordNet 1.5]

WordNet (r) 3.0 (2006):

apartheid
    n 1: a social policy or racial segregation involving political
         and economic and legal discrimination against people who
         are not Whites; the former official policy in South Africa

Moby Thesaurus II by Grady Ward, 1.0:

73 Moby Thesaurus words for "apartheid":
   Jim Crow, Jim Crow law, alien, anti-Semitism, apartness,
   black power, black supremacy, chauvinism, class consciousness,
   class distinction, class hatred, class prejudice, class war,
   color bar, color line, detachment, discrimination, division,
   ethnocentrism, exclusiveness, fascism, foreigner, insularity,
   insulation, isolation, isolationism, know-nothingism,
   male chauvinist, minority prejudice, narrowness, out-group,
   outcast, outsider, parochialism, persona non grata, privacy,
   privatism, privatization, quarantine, race hatred, race prejudice,
   race snobbery, racial discrimination, racial segregation,
   racialism, racism, recess, reclusion, red-baiting, retirement,
   retreat, rustication, seclusion, secrecy, segregation,
   separateness, separation, separatism, sequestration,
   sex discrimination, sexism, snobbishness, social barrier,
   social discrimination, splendid isolation, stranger,
   superpatriotism, tightness, ultranationalism, white power,
   white supremacy, withdrawal, xenophobia