Breadcrumb Home > Dictionary > Index O oct-: Meaning and Definition of Find definitions for: oct- Pronunciation: [key] var. oforbefore a vowel: octal. Oct. Pronunciation: [key] October. oct. Pronunciation: [key] octavo. Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. See also: oct- (Thesaurus) OCS octa- TrendingHere are the facts and trivia that people are buzzing about. Biographies: Notable Jewish Religious Leaders Current Events This Week: September 2023 Hispanic Population and the 2010 U.S. Census 50 Spookiest Halloween Quotes Preamble of the United Nations Charter The Jewish Calendar ✖ Related Content Daily Word Quiz: factotum Analogy of the Day: Today’s Analogy Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language