archaean
UK /ɑːˈkiːən/ · US /ɑɹˈkiːən/ noun, adjective, proper noun
Forms archaeans Archean Archæan
- noun (biology) Any organism of the domain Archaea.
- adjective (mythology) Of or relating to Arche, the Muse of beginnings in Greek mythology.
- adjective (geology) Of, or relating to the geologic eon from about 4,031 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.
- adjective (astronomy, "Archean" only) Of or relating to the irregular Jovian moon named for Arche.
- proper noun (geology) The eon from 2,500 Ma to 4,000 Ma.
Synonyms
Etymology
Archaea + -n
From Ancient Greek ἀρχαῖος (arkhaîos, “ancient”) (likely via Latin archaeus) + -an.
Webster’s 1913
Sources: Wiktionary · WordNet 3.0 · Webster’s 1913 — from the Wiktionary entry “archaean”, CC BY-SA 4.0. Details