Breadcrumb Home > Thesaurus > F Synonyms of fifteen Find synonyms for: Noun 1. fifteen, 15, XV, large integer usage: the cardinal number that is the sum of fourteen and one Adjective 1. fifteen, 15, xv, cardinal (vs. ordinal) usage: being one more than fourteen WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of fifteen (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Hanukkah Origins of the Christmas Holiday Jewish Holidays, 2010-2030 (A.M. 5770-5791) Western Christian Holidays, 2010-2030 Krampus: The Christmas Devil Kwanzaa ✖ Related Content Daily Word Quiz: eponymous Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language