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 examples are programmatically compiled from various online sources to illustrate current usage of the word 'octane number.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1931, in the meaning defined above

Time Traveler
The first known use of octane number was in 1931

Dictionary Entries Near octane number

Cite this Entry

“Octane number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/octane%20number. Accessed 26 Feb. 2024.

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