Meaning of ARCHEAN ERA

WordNet Dictionary
	Definition:		[n]  the time prior to 2,500 million years ago; earth's crust formed; unicellular organisms are earliest forms of life
	Synonyms:		Archaeozoic, Archaeozoic era, Archean, Archeozoic, Archeozoic era
	See Also:		era, geological era, Precambrian, Precambrian period