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English definition of “octane number”

octane number

noun [C]     (also octane rating)
a number showing the quality of petrol by representing how well and with how much power it can make an engine workMechanical engineeringPetroleum products especially when used as fuelFuels
(Definition of octane number noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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