Simple Definition of octane

from our Learner's Dictionary

octane

noun

ˈɑːkˌteɪn How to pronounce octane (audio)
: a chemical in petroleum that is used to rate the quality of different kinds of gasoline
an octane rating of 90

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“Octane.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/octane. Accessed 22 Jun. 2026.

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Britannica.com: Encyclopedia article about octane

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