from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun The ignition of fuel in an internal-combustion engine before the spark passes through the fuel, resulting from a hot spot in the cylinder or from too great a compression ratio for the fuel.

from The Century Dictionary.

  • noun An ignition of the combustible charge of fuel and air in an internal-combustion engine before the piston, on its compressing stroke, has reached the inner dead-center, or completed the normal compression of the charge. See ignition, 5.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (Engin.) Ignition in an internal-combustion engine while the inlet valve is open or before compression is completed.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun automotive The premature detonation of a fuel charge in Four-stroke cycle engines.


Sorry, no etymologies found.


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