/ Thesaurus / J Synonyms of john glenn Find synonyms for: Noun1. Glenn, John Glenn, John Herschel Glenn Jr.usage: made the first orbital rocket-powered flight by a United States astronaut in 1962; later in United States Senate (1921-)WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: panacea Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language