UN, the /ˌjuː ˈen/ BrE AmE abbreviation for
the United Nations; an international organization that almost every country in the world belongs to. It was started in 1945 to to try to find peaceful solutions to international problems and to make sure that countries work together to find peace. Its ↑ headquarters (=main offices) are in New York City. Other organizations that belong to the UN, such as the World Bank and the World Health Organization, are based in other places. Decisions at the UN are made by the General Assembly and the Security Council.
⇨ ↑ UN peacekeeping force