/ Thesaurus / F Synonyms of fire thorn Find synonyms for: Noun1. Pyracantha, pyracanth, fire thorn, firethorn, shrub, bushusage: any of various thorny shrubs of the genus Pyracantha bearing small white flowers followed by hard red or orange-red berriesWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: dormant Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language