spark plug

American  

noun

1. a device designed to fit in each cylinder of a gasoline-powered internal-combustion engine and to produce the electric spark for igniting the mixture of gasoline and air.

2. Informal. a person who leads, inspires, or animates a group.

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spark plug British  

noun

1. another name for sparking plug

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spark plug Scientific  

1. A device in the cylinder head of an internal-combustion engine that ignites the fuel mixture by means of an electric spark. Spark plugs consist of two electrodes that are separated by an insulator except at their tips. When high voltage electricity is fed to one electrode, it jumps across the gap from one tip to the other as a spark. The voltage required to generate a spark is directly proportional to the size of the gap; in a car engine it is about 18,000 volts.

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Etymology

Origin of spark plug

First recorded in 1900–05

Example Sentences

The maker of spark plugs and other auto parts collapsed with around $10 billion in debt in September.

From Barron's

That caused a short-circuit and "arcing" - electric sparks like those in a spark plug - which resulted in a "catastrophic failure".

From BBC

Char Miller, a professor of environmental history at Pomona College and author of “Burn Scars,” a history of U.S. wildfire suppression, said new development was the “spark plug” for many of the region’s fires.

From Los Angeles Times

Meanwhile, tune-ups, oil changes and spark plug replacements are now things of the past at the South Pasadena Police Department.

From Los Angeles Times

Lizotte, meanwhile, brings a different kind of energy as the Kings’ spark plug and emotional leader, especially on the penalty kill.

From Los Angeles Times