"RDJ" meaning in English

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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
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          "extra": "American actor and singer",
          "word": "Robert Downey Jr"
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          "langcode": "en",
          "name": "Individuals",
          "orig": "en:Individuals",
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            "Human",
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      "glosses": [
        "Initialism of Robert Downey Jr., American actor and singer."
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  "word": "RDJ"
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    {
      "args": {},
      "expansion": "RDJ",
      "name": "en-proper noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "alt_of": [
        {
          "extra": "American actor and singer",
          "word": "Robert Downey Jr"
        }
      ],
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        "English entries with incorrect language header",
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        "en:Individuals"
      ],
      "glosses": [
        "Initialism of Robert Downey Jr., American actor and singer."
      ],
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          "Robert Downey Jr.",
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        ]
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      "tags": [
        "abbreviation",
        "alt-of",
        "initialism"
      ]
    }
  ],
  "word": "RDJ"
}