"giga-annum" meaning in English

{
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      "args": {
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        "2": "giga-",
        "3": "annum"
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      "expansion": "giga- + annum",
      "name": "af"
    }
  ],
  "etymology_text": "giga- + annum",
  "forms": [
    {
      "form": "giga-annums",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
    {
      "args": {},
      "expansion": "giga-annum (plural giga-annums)",
      "name": "en-noun"
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  "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"
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          "source": "w"
        },
        {
          "kind": "other",
          "name": "English terms prefixed with giga-",
          "parents": [],
          "source": "w"
        },
        {
          "kind": "topical",
          "langcode": "en",
          "name": "Time",
          "orig": "en:Time",
          "parents": [
            "All topics",
            "Fundamental"
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      "examples": [
        {
          "ref": "2000, A. S. Weber, Nineteenth-Century Science: An Anthology, page 387",
          "text": "Geophysicists today estimate the earth’s age to be 4.5–4.6 Ga (giga-annums = 1 x 10⁹ years) based on data from lead isotopes (Dalrymple 403).",
          "type": "quotation"
        },
        {
          "ref": "2014, Sophia Ahmed et al., “A Haploid System of Sex Determination in the Brown Alga Ectocarpus sp.”, in Current Biology, volume 24, number 17, →DOI",
          "text": "We report here the sequencing and genomic analysis of the SDR of Ectocarpus, a brown alga that has been evolving independently from plants, animals, and fungi for over one giga-annum.",
          "type": "quotation"
        },
        {
          "ref": "2018, Ronald Martin, Earth’s Evolving Systems: The History of Planet Earth, 2nd edition, page 214",
          "text": "Possible cyanobacteria from the Apex charts of western Australia, which have been dated at ~3.5 (giga-annums, or billions of years).",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Gigayear, a billion years."
      ],
      "id": "en-giga-annum-en-noun-7bC-2yz4",
      "links": [
        [
          "Gigayear",
          "gigayear"
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        [
          "billion",
          "billion"
        ],
        [
          "year",
          "year"
        ]
      ],
      "synonyms": [
        {
          "word": "gigaannum"
        },
        {
          "tags": [
            "rare"
          ],
          "word": "gigannum"
        },
        {
          "tags": [
            "abbreviation"
          ],
          "word": "Ga"
        }
      ]
    }
  ],
  "word": "giga-annum"
}

{
  "etymology_templates": [
    {
      "args": {
        "1": "en",
        "2": "giga-",
        "3": "annum"
      },
      "expansion": "giga- + annum",
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    }
  ],
  "etymology_text": "giga- + annum",
  "forms": [
    {
      "form": "giga-annums",
      "tags": [
        "plural"
      ]
    }
  ],
  "head_templates": [
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      "expansion": "giga-annum (plural giga-annums)",
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  "lang": "English",
  "lang_code": "en",
  "pos": "noun",
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        "en:Time"
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          "ref": "2000, A. S. Weber, Nineteenth-Century Science: An Anthology, page 387",
          "text": "Geophysicists today estimate the earth’s age to be 4.5–4.6 Ga (giga-annums = 1 x 10⁹ years) based on data from lead isotopes (Dalrymple 403).",
          "type": "quotation"
        },
        {
          "ref": "2014, Sophia Ahmed et al., “A Haploid System of Sex Determination in the Brown Alga Ectocarpus sp.”, in Current Biology, volume 24, number 17, →DOI",
          "text": "We report here the sequencing and genomic analysis of the SDR of Ectocarpus, a brown alga that has been evolving independently from plants, animals, and fungi for over one giga-annum.",
          "type": "quotation"
        },
        {
          "ref": "2018, Ronald Martin, Earth’s Evolving Systems: The History of Planet Earth, 2nd edition, page 214",
          "text": "Possible cyanobacteria from the Apex charts of western Australia, which have been dated at ~3.5 (giga-annums, or billions of years).",
          "type": "quotation"
        }
      ],
      "glosses": [
        "Gigayear, a billion years."
      ],
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          "billion",
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        ],
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          "year",
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        ]
      ]
    }
  ],
  "synonyms": [
    {
      "word": "gigaannum"
    },
    {
      "tags": [
        "rare"
      ],
      "word": "gigannum"
    },
    {
      "tags": [
        "abbreviation"
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      "word": "Ga"
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  "word": "giga-annum"
}