Breadcrumb Home > Thesaurus > S Synonyms of sinclair Find synonyms for: Noun 1. Sinclair, Upton Sinclair, Upton Beall Sinclair usage: United States writer whose novels argued for social reform (1878-1968) 2. Sinclair, Clive Sinclair, Sir Clive Marles Sinclair usage: English electrical engineer who founded a company that introduced many innovative products (born in 1940) WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of sinclair (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Jewish Holidays, 2010-2030 (A.M. 5770-5791) Western Christian Holidays, 2010-2030 12 Steps to a New Year New Year's Resolution to Slim Down? Martin Luther King Speeches Books of the Bible: Old Testament Books in Order ✖ Related Content Daily Word Quiz: spurious Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language