/ Thesaurus / F Synonyms of four hundredth Find synonyms for: Adjective1. four-hundredth, 400th, ordinal (vs. cardinal)usage: the ordinal number of four hundred in counting orderWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: tactful Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language