Breadcrumb Home > Thesaurus > I Cite Synonyms of instantaneous Find synonyms for: Adjective1. instantaneous, instant(prenominal), fast (vs. slow)usage: occurring with no delay; "relief was instantaneous"; "instant gratification"WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.Definition and meaning of instantaneous (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. March 2021 Current Events: US News The Berlin Conference and the Partition of Africa The Implied Powers of Congress The Women's March on Versailles Keeping Your Brain Active in a COVID-19 World The Manchu Related Content Daily Word Quiz: punctilio Analogy of the Day: Today?s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language