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eon

eon
1. The largest geologic-time unit, incorporating a number of eras. The equivalent chronostratigraphic unit is the (little used) eonothem. Originally, two eons were proposed in 1930 by G. H. Chadwick. The younger was the Phanerozoic Eon (the time of evident life), comprising the Cenozoic, Mesozoic, and Palaeozoic Eras, and this term is still used. The term suggested for the preceding eon was the Cryptozoic (the time of hidden life). This time has also been called the Archaeozoic (the time of most ancient life), but most commonly has been known simply as the Precambrian. Three eons have been proposed for Precambrian time: the Priscoan for time before 4000 Ma ago; the Archaean for 4000–2500 Ma ago; and the Proterozoic for 2500–590 Ma ago; the term ‘Precambrian’ is still in frequent use but is informal.

2. A time unit of 109 present Earth years.

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"eon." A Dictionary of Ecology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"eon." A Dictionary of Ecology. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/eon-0

"eon." A Dictionary of Ecology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/eon-0

eon

eon
1. The largest geologic-time unit, incorporating a number of eras. The equivalent chronostratigraphic unit is the eonothem. Originally, two eons were proposed in 1930 by G. H. Chadwick. The younger was the Phanerozoic Eon (time of evident life), comprising the Cenozoic, Mesozoic, and Palaeozoic Eras, and this term is still used. The term suggested for the preceding eon was the Cryptozoic (time of hidden life). This time has also been called the Archaeozoic (time of most ancient life), but most commonly has been known simply as the Precambrian. Three eons have been proposed for Precambrian time: the Priscoan for time before 4000 Ma ago; the Archaean for 4000–2500 Ma ago; and the Proterozoic for 2500–590 Ma ago; the term ‘Precambrian’ is still in frequent use but is informal.

2. A time unit of 109 present Earth years.

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"eon." A Dictionary of Earth Sciences. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"eon." A Dictionary of Earth Sciences. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/eon

"eon." A Dictionary of Earth Sciences. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/science/dictionaries-thesauruses-pictures-and-press-releases/eon

eon

e·on / ˈēən; ˈēˌän/ (chiefly Brit. also ae·on) • n. (often eons) an indefinite and very long period of time, often a period exaggerated for humorous or rhetorical effect: he reached the crag eons before I arrived. ∎  Astron. & Geol. a unit of time equal to a billion years. ∎ Geol. a major division of geological time, subdivided into eras: the Precambrian eon. ∎  Philos. (in Neoplatonism, Platonism, and Gnosticism) a power existing from eternity; an emanation or phase of the supreme deity.

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"eon." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"eon." The Oxford Pocket Dictionary of Current English. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/eon-0

"eon." The Oxford Pocket Dictionary of Current English. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/eon-0

eon

eon see AEON.

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"eon." The Concise Oxford Dictionary of English Etymology. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"eon." The Concise Oxford Dictionary of English Etymology. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/eon-1

"eon." The Concise Oxford Dictionary of English Etymology. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/eon-1

eon

eonEritrean, Ghanaian, Himalayan, Malayan, Tigrayan •Actaeon, Aegean, aeon (US eon), Augean, Behan, Cadmean, Caribbean, Carolean, Chaldean, Cyclopean, empyrean, epicurean, European, Fijian, Galilean, Hasmonean, Hebridean, Herculean, Ian, Jacobean, Kampuchean, Laodicean, lien, Linnaean (US Linnean), Maccabean, Mandaean (US Mandean), Medicean, monogenean, Nabataean (US Nabatean), Orphean, paean, paeon, pean, peon, Periclean, piscean, plebeian, Pyrenean, Pythagorean, Sabaean, Sadducean, Sisyphean, skean, Tanzanian, Tennesseean, Terpsichorean, theodicean, Tyrolean

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"eon." Oxford Dictionary of Rhymes. . Encyclopedia.com. 18 Aug. 2017 <http://www.encyclopedia.com>.

"eon." Oxford Dictionary of Rhymes. . Encyclopedia.com. (August 18, 2017). http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/eon

"eon." Oxford Dictionary of Rhymes. . Retrieved August 18, 2017 from Encyclopedia.com: http://www.encyclopedia.com/humanities/dictionaries-thesauruses-pictures-and-press-releases/eon