Breadcrumb Home > Thesaurus > H Synonyms of horizontal Find synonyms for: Noun 1. horizontal, orientation usage: something that is oriented horizontally Adjective 1. horizontal (vs. vertical) (vs. inclined), crosswise, flat, level, naiant, swimming usage: parallel to or in the plane of the horizon or a base line; "a horizontal surface" WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of horizontal (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: bilious Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language