Archaean
English edit
Alternative forms edit
Etymology edit
From Ancient Greek ἀρχαῖα (arkhaîa, “ancient”), neuter plural of ἀρχαῖος (arkhaîos, “ancient”).
Pronunciation edit
- (Received Pronunciation) IPA(key): /ɑːˈkiːən/
Audio (Southern England) (file) - (General American) IPA(key): /ɑɹˈkiːən/
- Rhymes: -iən
Adjective edit
Archaean (not comparable)
- (geology) Of, or relating to the geologic eon from about 3,800 to 2,500 million years ago; comprises the Eoarchean, Paleoarchean, Mesoarchean and Neoarchean eras; marked by an atmosphere with little oxygen, the formation of the first continents and oceans and the emergence of simple life.
- 2006 March 25, NewScientist, page 12/1:
- The oldest vestiges of continental crust, which date from the Archaean aeon about 4 billion years ago, are in Acasta in north-west Canada.
Translations edit
of eon from 3,800 to 2,500 million years ago
Proper noun edit
Archaean
Hypernyms edit
- (eon 2,500–4,000 Ma): Precambrian
Hyponyms edit
- (eon 2,500–4,000 Ma): Eoarchaean, Paleoarchaean, Mesoarchaean, Neoarchaean
Coordinate terms edit
- (eon 2,500–4,000 Ma): Hadean, Proterozoic - eons in Precambrian
Translations edit
Archaean eon
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