/ Thesaurus / H Synonyms of hadean eon Find synonyms for: Noun1. Hadean, Hadean time, Hadean eon, Hadean aeon, Priscoan, Priscoan eon, Priscoan aeonusage: 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 lifeWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: profiterole Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language