archean

Adjective

• of or relating to the earliest known rocks formed during the Precambrian Eon

Noun

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

Related words

• Synonyms: 
  archaean , Archean , Archean eon , Archean aeon , Archeozoic , Archaeozoic , Archeozoic eon , Archaeozoic aeon