/ Thesaurus / P Synonyms of pius ix Find synonyms for: Noun1. Pius IX, Giovanni Mastai-Ferretti, Giovanni Maria Mastai-Ferrettiusage: Italian pope from 1846 to 1878 who in 1854 declared the dogma of the Immaculate Conception of the Virgin MaryWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: effervescent Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language