octane number


Definition of octane number

: a number that is used to measure the antiknock properties of a liquid motor fuel (such as gasoline) with a higher number indicating a smaller likelihood of knocking

called also octane rating

— compare cetane number

Examples of octane number in a Sentence

Recent Examples on the Web The higher the octane number, the more stable the fuel. Courtney Linder, Popular Mechanics, 22 Mar. 2022 Fueling requires unleaded pump octane number (PON) 86 or higher. Joe Michaud, San Diego Union-Tribune, 16 Aug. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'octane number.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of octane number

1931, in the meaning defined above

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The first known use of octane number was in 1931

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Cite this Entry

“Octane number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/octane%20number. Accessed 16 Aug. 2022.

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More from Merriam-Webster on octane number

Britannica.com: Encyclopedia article about octane number


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