/ Thesaurus / Q Synonyms of quadratic equation Find synonyms for: Noun1. quadratic equation, quadratic, equationusage: an equation in which the highest power of an unknown quantity is a squareWordNet 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