geologic time, geological time - the time of the physical formation and development of the earth (especially prior to human history)

geological era, era - a major division of geological time; an era is usually divided into two or more periods

Phanerozoic, Phanerozoic aeon, Phanerozoic eon - the period from about 5,400 million years ago until the present

Precambrian, Precambrian aeon, Precambrian eon, Precambrian period - the eon following the Hadean time and preceding the Phanerozoic eon; from about 3,800 million years ago until 544 million years ago

Proterozoic, Proterozoic aeon, Proterozoic eon - from 2,500 to 544 million years ago; bacteria and fungi; primitive multicellular organisms

Archaeozoic, Archaeozoic aeon, Archean, Archean aeon, Archean eon, Archeozoic, Archeozoic eon - the time from 3,800 million years to 2,500 million years ago; earth's crust formed; unicellular organisms are earliest forms of life

Hadean, Hadean aeon, Hadean eon, Hadean time, Priscoan, Priscoan aeon, Priscoan eon - the earliest eon in the history of the Earth from the first accretion of planetary material (around 4,600 million years ago) until the date of the oldest known rocks (about 3,800 million years ago); no evidence of life

long time, years, age - a prolonged period of time; "we've known each other for ages"; "I haven't been there for years and years"

Gnosticism - a religious orientation advocating gnosis as the way to release a person's spiritual element; considered heresy by Christian churches

spiritual being, supernatural being - an incorporeal being believed to have powers to affect the course of human events