/ Thesaurus / R Synonyms of runner up Find synonyms for: Noun1. runner-up, second best, rival, challenger, competitor, competition, contenderusage: the competitor who finishes secondWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: abominable Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language