WordNet (r) 3.0 (2006):

Interpol
    n 1: an international intelligence agency permitting
         collaboration among intelligence agencies around the world

Moby Thesaurus II by Grady Ward, 1.0:

62 Moby Thesaurus words for "Interpol":
   AL, ANZUS Council, ASPAC, Arab League, BIS, British Commonwealth,
   CACM, CENTO, Central Treaty Organization, Cheka, Colombo Plan,
   Common Market, Commonwealth of Nations, Council of Europe, ECSC,
   EEC, EFTA, Euratom, European Economic Community, FBI,
   French Community, Gestapo, ICRC, LAFTA, MP, MVD, Mounties, NATO,
   NKVD, Nordic Council, OAS, OAU, OCAM, OECD, OGPU, OPEC, RCMP,
   SEATO, SP, Scotland Yard, WCC, Warsaw Pact, constabulary,
   county police, highway patrol, law enforcement agency,
   military police, police, police force, political police, posse,
   provincial police, riot police, secret police, security force,
   shore patrol, special police, state police, tactical police,
   troopers, vigilance committee, vigilantes