octane number

noun

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

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 3 Jul. 2020.

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Britannica.com: Encyclopedia article about octane number

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