/ Thesaurus / O Synonyms of octane number Find synonyms for: Noun1. octane number, octane rating, measure, quantity, amountusage: a measure of the antiknock properties of gasolineWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: devout Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language