"megafossil" meaning in English

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "mega",
        "3": "fossil"
      },
      "expansion": "mega- + fossil",
      "name": "prefix"
    }
  ],
  "etymology_text": "mega- + fossil",
  "forms": [
    {
      "form": "megafossils",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "megafossil (plural megafossils)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "senses": [
    {
      "categories": [
        {
          "kind": "other",
          "name": "English entries with incorrect language header",
          "parents": [
            "Entries with incorrect language header",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English entries with topic categories using raw markup",
          "parents": [
            "Entries with topic categories using raw markup",
            "Entry maintenance"
          ],
          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms prefixed with mega-",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Paleontology",
          "orig": "en:Paleontology",
          "parents": [
            "Geology",
            "Sciences",
            "Earth sciences",
            "All topics",
            "Fundamental"
          ],
          "source": "w"
        }
      ],
      "glosses": [
        "A relatively large fossil showing the structure of an organism."
      ],
      "id": "en-megafossil-en-noun-yoGVMiPD",
      "links": [
        [
          "fossil",
          "fossil"
        ],
        [
          "structure",
          "structure"
        ],
        [
          "organism",
          "organism"
        ]
      ],
      "related": [
        {
          "word": "microfossil"
        }
      ]
    }
  ],
  "word": "megafossil"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "mega",
        "3": "fossil"
      },
      "expansion": "mega- + fossil",
      "name": "prefix"
    }
  ],
  "etymology_text": "mega- + fossil",
  "forms": [
    {
      "form": "megafossils",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "megafossil (plural megafossils)",
      "name": "en-noun"
    }
  ],
  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
  "related": [
    {
      "word": "microfossil"
    }
  ],
  "senses": [
    {
      "categories": [
        "English countable nouns",
        "English entries with incorrect language header",
        "English entries with topic categories using raw markup",
        "English lemmas",
        "English nouns",
        "English terms prefixed with mega-",
        "en:Paleontology"
      ],
      "glosses": [
        "A relatively large fossil showing the structure of an organism."
      ],
      "links": [
        [
          "fossil",
          "fossil"
        ],
        [
          "structure",
          "structure"
        ],
        [
          "organism",
          "organism"
        ]
      ]
    }
  ],
  "word": "megafossil"
}