"an egg's age" meaning in English

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      "expansion": "an egg's age",
      "name": "en-noun"
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "American English",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
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      "examples": [
        {
          "ref": "1922, Thomas Lansing Masson, Our American Humorists, page 201",
          "text": "Nothing about my natural charms no more, an egg's age since anybody had called me to 1 side and whispered \"I got a T. L. for you. Gertie thinks your ears is immense.\"",
          "type": "quotation"
        },
        {
          "ref": "1928, New York Herald Tribune Books, volume 4, numbers 1-11, page 21",
          "text": "As entertaining a book as you will find in an egg's age.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A very long time."
      ],
      "id": "en-an_egg's_age-en-noun-o~hqJZEz",
      "raw_glosses": [
        "(US, slang, dated) A very long time."
      ],
      "tags": [
        "US",
        "dated",
        "slang"
      ]
    }
  ],
  "word": "an egg's age"
}

{
  "head_templates": [
    {
      "args": {
        "1": "?"
      },
      "expansion": "an egg's age",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        "American English",
        "English countable nouns",
        "English dated terms",
        "English entries with incorrect language header",
        "English lemmas",
        "English multiword terms",
        "English nouns",
        "English nouns with unknown or uncertain plurals",
        "English slang",
        "English terms with quotations"
      ],
      "examples": [
        {
          "ref": "1922, Thomas Lansing Masson, Our American Humorists, page 201",
          "text": "Nothing about my natural charms no more, an egg's age since anybody had called me to 1 side and whispered \"I got a T. L. for you. Gertie thinks your ears is immense.\"",
          "type": "quotation"
        },
        {
          "ref": "1928, New York Herald Tribune Books, volume 4, numbers 1-11, page 21",
          "text": "As entertaining a book as you will find in an egg's age.",
          "type": "quotation"
        }
      ],
      "glosses": [
        "A very long time."
      ],
      "raw_glosses": [
        "(US, slang, dated) A very long time."
      ],
      "tags": [
        "US",
        "dated",
        "slang"
      ]
    }
  ],
  "word": "an egg's age"
}