"Underground Railroad" meaning in English

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      "form": "Underground Railway",
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  "lang": "English",
  "lang_code": "en",
  "pos": "name",
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          "name": "Slavery",
          "orig": "en:Slavery",
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          "langcode": "en",
          "name": "Transport",
          "orig": "en:Transport",
          "parents": [
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        }
      ],
      "glosses": [
        "The pre-American Civil War anti-slavery resistance movement dedicated to helping escaped slaves to reach safe territory."
      ],
      "id": "en-Underground_Railroad-en-name-PY~fmS8l",
      "links": [
        [
          "slavery",
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        ],
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        ]
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      "raw_glosses": [
        "(historical) The pre-American Civil War anti-slavery resistance movement dedicated to helping escaped slaves to reach safe territory."
      ],
      "tags": [
        "historical"
      ],
      "wikipedia": [
        "Underground Railroad"
      ]
    }
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  "word": "Underground Railroad"
}

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    {
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      "form": "Underground Railway",
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  "lang_code": "en",
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        "The pre-American Civil War anti-slavery resistance movement dedicated to helping escaped slaves to reach safe territory."
      ],
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          "resistance",
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      ],
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