"Underground" meaning in English

{
  "forms": [
    {
      "form": "the Underground",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "head": "the Underground"
      },
      "expansion": "the Underground",
      "name": "en-proper noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "British English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
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          "source": "w"
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          "name": "Pages with 2 entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "place",
          "langcode": "en",
          "name": "London",
          "orig": "en:London",
          "parents": [
            "Cities in England",
            "Cities in Greater London, England",
            "Cities in the United Kingdom",
            "Cities",
            "Places",
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            "All topics",
            "Proper nouns",
            "Terms by semantic function",
            "Fundamental",
            "Nouns",
            "Lemmas"
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          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Rail transportation",
          "orig": "en:Rail transportation",
          "parents": [
            "Transport",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "examples": [
        {
          "ref": "1940 October, “Notes and News: The High Barnet Branch”, in Railway Magazine, page 569:",
          "text": "Although some of the stations on ' The Branch ' have not, as yet, suffered any considerable structural alterations, all are now equipped with the familiar Underground type name boards, and as a result the imposing titles of G.N. days have been ruthlessly curtailed.",
          "type": "quote"
        },
        {
          "ref": "2019 October, John Glover, “Heathrow rail expansion”, in Modern Railways, page 71:",
          "text": "Heathrow has a 28% share of passengers arriving by rail, two-thirds of whom come by the Underground.",
          "type": "quote"
        }
      ],
      "glosses": [
        "The London Underground."
      ],
      "id": "en-Underground-en-name-nS2AE~Ha",
      "links": [
        [
          "rail transport",
          "rail transport"
        ],
        [
          "London Underground",
          "London Underground"
        ]
      ],
      "raw_glosses": [
        "(UK, rail transport) The London Underground."
      ],
      "related": [
        {
          "word": "Overground"
        }
      ],
      "synonyms": [
        {
          "word": "Tube"
        }
      ],
      "tags": [
        "UK"
      ],
      "topics": [
        "rail-transport",
        "railways",
        "transport"
      ]
    }
  ],
  "word": "Underground"
}

{
  "forms": [
    {
      "form": "the Underground",
      "tags": [
        "canonical"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {
        "head": "the Underground"
      },
      "expansion": "the Underground",
      "name": "en-proper noun"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "name",
  "related": [
    {
      "word": "Overground"
    }
  ],
  "senses": [
    {
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        "British English",
        "English entries with incorrect language header",
        "English lemmas",
        "English proper nouns",
        "English terms with quotations",
        "English uncountable nouns",
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        "en:London",
        "en:Rail transportation"
      ],
      "examples": [
        {
          "ref": "1940 October, “Notes and News: The High Barnet Branch”, in Railway Magazine, page 569:",
          "text": "Although some of the stations on ' The Branch ' have not, as yet, suffered any considerable structural alterations, all are now equipped with the familiar Underground type name boards, and as a result the imposing titles of G.N. days have been ruthlessly curtailed.",
          "type": "quote"
        },
        {
          "ref": "2019 October, John Glover, “Heathrow rail expansion”, in Modern Railways, page 71:",
          "text": "Heathrow has a 28% share of passengers arriving by rail, two-thirds of whom come by the Underground.",
          "type": "quote"
        }
      ],
      "glosses": [
        "The London Underground."
      ],
      "links": [
        [
          "rail transport",
          "rail transport"
        ],
        [
          "London Underground",
          "London Underground"
        ]
      ],
      "raw_glosses": [
        "(UK, rail transport) The London Underground."
      ],
      "synonyms": [
        {
          "word": "Tube"
        }
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      "tags": [
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      "topics": [
        "rail-transport",
        "railways",
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  "word": "Underground"
}