/ Thesaurus / F Synonyms of fulvic acid Find synonyms for: Noun1. fulvic acid, humic substanceusage: a yellow to yellow-brown humic substance that is soluble in water under all pH conditions; "they measured the fluvial fulvic acid"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: tenacious Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language