"below ground" meaning in English

{
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        "2": "prepositional phrase",
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      "expansion": "below ground",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "below ground",
      "name": "en-PP"
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  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "prep_phrase",
  "senses": [
    {
      "alt_of": [
        {
          "word": "belowground"
        }
      ],
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          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
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          "source": "w"
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      "examples": [
        {
          "ref": "1960 December, “The Glasgow Suburban Electrification is opened”, in Trains Illustrated, page 713",
          "text": "The station has been refurbished both at ground level and below ground, where the wide, fluorescently lit platforms are an almost unrecognisable metamorphosis of the dingy, reeking Low Level of old.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative form of belowground"
      ],
      "id": "en-below_ground-en-prep_phrase-~wZgSZU6",
      "links": [
        [
          "belowground",
          "belowground#English"
        ]
      ],
      "tags": [
        "alt-of",
        "alternative"
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    }
  ],
  "sounds": [
    {
      "rhymes": "-aʊnd"
    }
  ],
  "word": "below ground"
}

{
  "head_templates": [
    {
      "args": {
        "1": "en",
        "2": "prepositional phrase",
        "head": ""
      },
      "expansion": "below ground",
      "name": "head"
    },
    {
      "args": {},
      "expansion": "below ground",
      "name": "en-PP"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "prep_phrase",
  "senses": [
    {
      "alt_of": [
        {
          "word": "belowground"
        }
      ],
      "categories": [
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English prepositional phrases",
        "English terms with quotations",
        "Rhymes:English/aʊnd",
        "Rhymes:English/aʊnd/3 syllables"
      ],
      "examples": [
        {
          "ref": "1960 December, “The Glasgow Suburban Electrification is opened”, in Trains Illustrated, page 713",
          "text": "The station has been refurbished both at ground level and below ground, where the wide, fluorescently lit platforms are an almost unrecognisable metamorphosis of the dingy, reeking Low Level of old.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Alternative form of belowground"
      ],
      "links": [
        [
          "belowground",
          "belowground#English"
        ]
      ],
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        "alt-of",
        "alternative"
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    }
  ],
  "sounds": [
    {
      "rhymes": "-aʊnd"
    }
  ],
  "word": "below ground"
}