"United Nations" is a descriptor in the National Library of Medicine's controlled vocabulary thesaurus, MeSH (Medical Subject Headings). Descriptors are arranged in a hierarchical structure, which enables searching at various levels of specificity.
Below are MeSH descriptors whose meaning is more general than "United Nations".
Below are MeSH descriptors whose meaning is related to "United Nations".
Below are MeSH descriptors whose meaning is more specific than "United Nations".