"Underground Railroad" meaning in English

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  "lang_code": "en",
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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",
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          "resistance",
          "resistance"
        ],
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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."
      ],
      "synonyms": [
        {
          "word": "Underground Railway"
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  "word": "Underground Railroad"
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  "word": "Underground Railroad"
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