archean
- (s) of or relating to the earliest known rocks formed during the Precambrian Eon archaean,
Nouns
- (n) the time from 3,800 million years to 2,500 million years ago; earth's crust formed; unicellular organisms are earliest forms of life Archaeozoic, Archaeozoic aeon, Archean aeon, Archean eon, Archeozoic, Archeozoic eon,