"main earth" meaning in English

{
  "forms": [
    {
      "form": "main earths",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "main earth (plural main earths)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "attestations": [
        {
          "date": "from 19th c.",
          "references": []
        }
      ],
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "Pages with 1 entry",
          "parents": [],
          "source": "w"
        },
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          "kind": "other",
          "name": "Pages with entries",
          "parents": [],
          "source": "w"
        }
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      "examples": [
        {
          "bold_text_offsets": [
            [
              42,
              52
            ]
          ],
          "ref": "1928, Siegfried Sassoon, Memoirs of a Fox-Hunting Man, Penguin, published 2013, page 24:",
          "text": "‘What the hell do you mean by leaving the main-earth unstopped?’ the infuriated voice continued.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A fox's primary lair."
      ],
      "id": "en-main_earth-en-noun-w2Ulcmjr",
      "links": [
        [
          "fox",
          "fox"
        ],
        [
          "lair",
          "lair"
        ]
      ],
      "qualifier": "fox hunting",
      "raw_glosses": [
        "(fox hunting) A fox's primary lair."
      ]
    }
  ],
  "word": "main earth"
}

{
  "forms": [
    {
      "form": "main earths",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "main earth (plural main earths)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "attestations": [
        {
          "date": "from 19th c.",
          "references": []
        }
      ],
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English terms with quotations",
        "Pages with 1 entry",
        "Pages with entries",
        "Quotation templates to be cleaned"
      ],
      "examples": [
        {
          "bold_text_offsets": [
            [
              42,
              52
            ]
          ],
          "ref": "1928, Siegfried Sassoon, Memoirs of a Fox-Hunting Man, Penguin, published 2013, page 24:",
          "text": "‘What the hell do you mean by leaving the main-earth unstopped?’ the infuriated voice continued.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A fox's primary lair."
      ],
      "links": [
        [
          "fox",
          "fox"
        ],
        [
          "lair",
          "lair"
        ]
      ],
      "qualifier": "fox hunting",
      "raw_glosses": [
        "(fox hunting) A fox's primary lair."
      ]
    }
  ],
  "word": "main earth"
}