Meaning of GEOLOGICAL ERA

WordNet Dictionary
	Definition:		[n]  a major division of geological time; an era is usually divided into two or more periods
	Synonyms:		era
	See Also:		aeon, Age of Mammals, Age of Reptiles, Archaeozoic, Archaeozoic era, Archean, Archean era, Archeozoic, Archeozoic era, Cenozoic, Cenozoic era, eon, geologic time, geological period, geological time, Mesozoic, Mesozoic era, Paleozoic, Paleozoic era, period, Precambrian, Precambrian period, Preoterozoic era, Proterozoic