/ Thesaurus / F Synonyms of frederick william i Find synonyms for: Noun1. Frederick William Iusage: son of Frederick I who became king of Prussia in 1713; reformed and strengthened the Prussian army (1688-1740)WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: inane Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language