"RSDLP" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Russian Social Democratic Labour Party"
        }
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          "kind": "topical",
          "langcode": "en",
          "name": "Politics",
          "orig": "en:Politics",
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            "Society",
            "All topics",
            "Fundamental"
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          "source": "w"
        }
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      "glosses": [
        "Initialism of Russian Social Democratic Labour Party."
      ],
      "id": "en-RSDLP-en-name-Rf4BZddk",
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        [
          "politics",
          "politics"
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          "Russian Social Democratic Labour Party",
          "w:Russian Social Democratic Labour Party"
        ]
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        "(politics, historical) Initialism of Russian Social Democratic Labour Party."
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "historical",
        "initialism"
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      "topics": [
        "government",
        "politics"
      ]
    }
  ],
  "word": "RSDLP"
}

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      "expansion": "RSDLP",
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "word": "Russian Social Democratic Labour Party"
        }
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        "English entries with incorrect language header",
        "English initialisms",
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        "English proper nouns",
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        "Pages with 1 entry",
        "Pages with entries",
        "en:Politics"
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        "Initialism of Russian Social Democratic Labour Party."
      ],
      "links": [
        [
          "politics",
          "politics"
        ],
        [
          "Russian Social Democratic Labour Party",
          "w:Russian Social Democratic Labour Party"
        ]
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        "(politics, historical) Initialism of Russian Social Democratic Labour Party."
      ],
      "tags": [
        "abbreviation",
        "alt-of",
        "historical",
        "initialism"
      ],
      "topics": [
        "government",
        "politics"
      ]
    }
  ],
  "word": "RSDLP"
}