"River of Doubt" meaning in All languages combined

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  "lang": "English",
  "lang_code": "en",
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        {
          "kind": "place",
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          "name": "Rivers in South America",
          "orig": "en:Rivers in South America",
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      "glosses": [
        "A river in South America, part of the Amazon watershed, now named the Roosevelt River following exploration of it by a party including Theodore Roosevelt."
      ],
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          "Amazon",
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        "(sometimes attributive) A river in South America, part of the Amazon watershed, now named the Roosevelt River following exploration of it by a party including Theodore Roosevelt."
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        "A river in South America, part of the Amazon watershed, now named the Roosevelt River following exploration of it by a party including Theodore Roosevelt."
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        "(sometimes attributive) A river in South America, part of the Amazon watershed, now named the Roosevelt River following exploration of it by a party including Theodore Roosevelt."
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