/ Thesaurus / I Synonyms of if not Find synonyms for: Adverb1. if notusage: perhaps; indicating possibility of being more remarkable (greater or better or sooner) than; "will yield 10% if not more"; "pretty if not actually beautiful"; "let's meet tonight if not sooner"WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: penury Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language