Breadcrumb Home > Thesaurus > O Synonyms of oto Find synonyms for: Noun 1. Oto, Otoe, Sioux, Siouan usage: a member of the Siouan people inhabiting the valleys of the Platte and Missouri rivers in Nebraska 2. Oto, Otoe, Chiwere usage: a dialect of the Chiwere language spoken by the Oto WordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved.Definition and meaning of oto (Dictionary) TrendingHere are the facts and trivia that people are buzzing about. Hanukkah Origins of the Christmas Holiday Jewish Holidays, 2010-2030 (A.M. 5770-5791) Western Christian Holidays, 2010-2030 Krampus: The Christmas Devil Kwanzaa ✖ Related Content Daily Word Quiz: tintinnabulation Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language