/ Thesaurus / 1 Synonyms of 1840s Find synonyms for: Noun1. 1840s, decade, decennary, decenniumusage: the decade from 1840 to 1849WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: labyrinth Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language