/ Thesaurus / O Synonyms of on base Find synonyms for: Adverb1. aboard, on baseusage: on first or second or third base; "Their second homer with Bob Allison aboard"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: pristine Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language