a fuels ability to resist 'predetonation' or 'pinginging' as it is also called

The octane rating of a fuel is indicated on the pump—using numbers such as 87, 90, 91, etc. The higher the number, the greater the octane rating of the gasoline. The octane rating represents the "antiknock" properties of the fuel. The higher the number, the slower the fuel burns—and the less likely your engine will knock. Ethanol typically adds two to three octane numbers when blended with ordinary gasoline—making it a cost-effective octane-enhancer.

a measure of the performance of gasoline. A high octane rating gives efficient ignition.

A number indicating the quality of gasoline based on its ability to resist knock. The higher the number, the better the quality. Higher compression engines require higher octane gas.

The octane rating is the measure of a gasolineâ€(tm)s resistance to exploding too early in the engine cycle, which causes knocking. In other words, a number used to indicate gasoline's antiknock performance in motor vehicle engines. The higher the octane rating, the lower the chance of premature ignition. The two recognized laboratory engine test methods for determining the antiknock rating, i.e., octane rating, of gasoline grades are the Research method and the Motor method. To provide a single number as guidance to the consumer, the antiknock index (R + M)/2, which is the average of the Research and Motor octane numbers, was developed.

A method of rating gasoline by measuring its ability to resist knocking, or pinging, in internal combustion engines. Engines with higher compression ratios require higheroctane gasoline.

The anti-knock index number of a fuel

A measure of a fuel's resistance to self ignition, hence a measure as well of the antiknock properties of the fuel.  Pump Octane: The octane as posted on retail gasoline dispensers as (R+M)/2; same as Antiknock Index.  Motor Octane: The octane as tested in a single-cylinder octane test engine at more severe operating conditions. Motor Octane Number (MON) affects high-speed and part-throttle knock and performance under load, passing, climbing and other operating conditions. Motor octane is represented by the designation M in the (R+M)/2 equation and is the lower of the two numbers.  Research Octane Number (RON): The octane as tested in a single-cylinder octane test engine operated under less severe operating conditions. RON affects low- to medium-speed knock and engine run-on. Research Octane is presented by the designation R in the (R+M)/2 equation and is the higher of the two numbers.

A term used for octane number.

A quality specification for gasoline that measures its tendency to ignite spontaneously creating engine knock and causing the engine to operate less efficiently. Two basic rating systems exist: the research octane number, or RON, and the motor octane number, or MON. In both cases a higher number means better quality. Lead has traditionally been used as a low-cost additive to raise the octane number of gasoline, but it has been banned in many countries for health reasons, requiring the use of other high-octane additives.

The octane rating is a measure of the autoignition resistance of gasoline (petrol) and other fuels used in spark-ignition internal combustion engines. It's a measure of anti-detonation of a gasoline or fuel.