"UPU" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Universal Postal Union"
        }
      ],
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        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
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          "source": "w"
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          "source": "w"
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          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Organizations",
          "orig": "en:Organizations",
          "parents": [
            "Society",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Philately",
          "orig": "en:Philately",
          "parents": [
            "Hobbies",
            "Recreation",
            "Human activity",
            "Human behaviour",
            "Human",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "United Nations",
          "orig": "en:United Nations",
          "parents": [
            "Organizations",
            "Society",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "Initialism of Universal Postal Union."
      ],
      "id": "en-UPU-en-name-oNndQ1qT",
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        [
          "Universal Postal Union",
          "Universal Postal Union#English"
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        "abbreviation",
        "alt-of",
        "initialism"
      ],
      "wikipedia": [
        "UPU"
      ]
    }
  ],
  "word": "UPU"
}

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      "args": {},
      "expansion": "UPU",
      "name": "en-proper noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Universal Postal Union"
        }
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        "English entries with incorrect language header",
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        "Pages with entries",
        "en:Organizations",
        "en:Philately",
        "en:United Nations"
      ],
      "glosses": [
        "Initialism of Universal Postal Union."
      ],
      "links": [
        [
          "Universal Postal Union",
          "Universal Postal Union#English"
        ]
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "initialism"
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      "wikipedia": [
        "UPU"
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  "word": "UPU"
}