1. OAU Convention refugees (< Refugees)

    https://thesaurus.ecoi.net/ec270

  2. Obe (< Herat)

    https://thesaurus.ecoi.net/_a050b228

    District in Herat Province

  3. Obo (< Haut-Mbomou)

    https://thesaurus.ecoi.net/_e2eeb5fc

    Capital of Haut-Mbomou prefecture

  4. Observatoire Haïtien des crimes contre l’humanité (< Groups in Haiti)

    https://thesaurus.ecoi.net/_a2e35f44

    Organisation dedicated to monitoring, documenting and reporting crimes against humanity in Haiti

  5. Occitan (< Languages)

    https://thesaurus.ecoi.net/huridocs-mt14150303090101

    spoken since 1500

  6. Occupational diseases (< Public health)

    https://thesaurus.ecoi.net/ec1656

  7. Occupational medicine (< Medical specialties)

    https://thesaurus.ecoi.net/ec1705

  8. occupational physicians (< Occupational medicine, physicians)

    https://thesaurus.ecoi.net/ec1728

  9. Occupations (< Employment)

    https://thesaurus.ecoi.net/ec952

  10. Occupied Palestinian Territory (< Western Asia)

    https://thesaurus.ecoi.net/huridocs-mt15030545

  11. Oceania (< Geographical areas)

    https://thesaurus.ecoi.net/huridocs-mt1505

  12. Ocnita (< Republic of Moldova)

    https://thesaurus.ecoi.net/_3ce3c577

    District (raion) in Moldova

  13. Ocnita (< Ocnita)

    https://thesaurus.ecoi.net/_66c11494

    Capital of Ocnita district (raion)

  14. Odesa (< Odesa oblast)

    https://thesaurus.ecoi.net/_7835f718

    Capital of Odesa Oblast

  15. Odesa oblast (< Ukraine)

    https://thesaurus.ecoi.net/_241d15b8

    Oblast in Ukraine

  16. Odhikar (< Groups in Bangladesh)

    https://thesaurus.ecoi.net/_00003895

    Human rights organisation

  17. Odienné (< Denguélé)

    https://thesaurus.ecoi.net/_451d5e00

    Capital of Denguélé

  18. Odisha (< India)

    https://thesaurus.ecoi.net/ec2596

    State in India

  19. Official languages (< Language)

    https://thesaurus.ecoi.net/ec1185

  20. Offspring (< family members)

    https://thesaurus.ecoi.net/ec1268

  21. Oficina de Asistencia al Migrante Retornado (< Groups in Honduras)

    https://thesaurus.ecoi.net/_a1608741

    Office in Honduras specialised on assistance for migrants who want to return to their country of origin

  22. Ogaden (< Groups in Somalia)

    https://thesaurus.ecoi.net/_9f7f7f1e

    Clan

  23. Ogaden National Liberation Front (< Groups in Ethiopia)

    https://thesaurus.ecoi.net/_0e154ad2

    Separatist rebel group

  24. Ogun (< Nigeria)

    https://thesaurus.ecoi.net/ec2283

    Bundesstaat in Nigeria

  25. Ohrid (< Southwestern)

    https://thesaurus.ecoi.net/_f509926c

    Capital of Southwestern Statistical Region

  26. Ojibwa (< Languages)

    https://thesaurus.ecoi.net/huridocs-mt14151009022301

  27. Okinawans (< Ethnic groups and nationalities)

    https://thesaurus.ecoi.net/huridocs-mt13151109140101

  28. Old caseload refugees (< Refugees)

    https://thesaurus.ecoi.net/ec271

    These include many (Rwandese) refugees whose cases pre-date 1994. Their cases are frequently referred to as "old caseload". The vast majority of these individuals were so-called old caseload refugees who had settled in the country during the 35 years prior to 1994 when Tanzanian authorities had an "open door" policy towards refugees.

  29. Old-age benefits (< Benefits)

    https://thesaurus.ecoi.net/ec1380

  30. Oman (< Western Asia)

    https://thesaurus.ecoi.net/huridocs-mt15030543

  31. Omanis (< Ethnic groups and nationalities)

    https://thesaurus.ecoi.net/ec2025

  32. Ombella-M’Poko (< Central African Republic)

    https://thesaurus.ecoi.net/_3d74c8a1

    Prefecture in the Central African Republic

  33. Omna (< Paktika)

    https://thesaurus.ecoi.net/_8407697d

    District in Paktika Province

  34. Omo People’s Democratic Union (< Groups in Ethiopia)

    https://thesaurus.ecoi.net/_2096d443

    Political party

  35. OMON (< Groups in Russia)

    https://thesaurus.ecoi.net/_cfae5c7b

    Special police unit

  36. Omsk (< Omsk oblast)

    https://thesaurus.ecoi.net/_5cef16d8

    Administrative Center of Omsk oblast

  37. Omsk oblast (< Siberian Federal District)

    https://thesaurus.ecoi.net/_87e29a15

    Administrative division in Siberian Federal District in Russia

  38. Oncologists (< Oncology, physicians)

    https://thesaurus.ecoi.net/ec1740

  39. Oncology (< Internal medicine)

    https://thesaurus.ecoi.net/ec1723

  40. Ondo (< Nigeria)

    https://thesaurus.ecoi.net/ec2284

    State in Nigeria