/ Thesaurus / I Synonyms of interest rate Find synonyms for: Noun1. interest rate, rate of interest, rate, charge per unitusage: the percentage of a sum of money charged for its useWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: spectral Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language