the time from 3, 800 million years to 2, 500 million years ago; earths crust formed; unicellular organisms are earliest forms of life

[ Syn: archean , archean eon , archean aeon , archeozoic , archaeozoic , archeozoic eon , archaeozoic aeon ]

of or belonging to earlier of two divisions of the Precambrian era; archeozoic life forms

[ Syn: archaeozoic ]