archeozoic_era has definitions from the field of geology
1
[ noun ] (geology) the time prior to 2,500 million years ago; earth's crust formed; unicellular organisms are earliest forms of life

Related terms

era Precambrian

2
[ noun ] (geology) the time from 1.5 billion to 5 billion years ago; earth's crust formed; unicellular organisms are earliest forms of life

Related terms

eon era Precambrian

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