Definitions

1. adjective

relating to or denoting the earliest phase of the Earth’s history, from about 3.5 to 2.5 billion years ago

“The geologists were studying the archeozoic rocks in the field.”

2. noun

the earliest phase of the Earth’s history, from about 3.5 to 2.5 billion years ago

“The archeozoic era was characterized by the formation of the Earth’s crust.”

3. noun

a division of the Precambrian period, from about 3.5 to 2.5 billion years ago

“The archeozoic era was a time of intense volcanic activity.”