spark plug

noun
Updated on: 16 Nov 2017

Definition of spark plug

1 :a part that fits into the cylinder head of an internal combustion engine and carries two electrodes separated by an air gap across which the current from the ignition system discharges to form the spark for combustion
2 :one that initiates or gives impetus to an undertaking

sparkplug

play \ˈspärk-ˌpləg\ transitive verb

Recent Examples of spark plug from the Web

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'spark plug.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of spark plug

1903


SPARK PLUG Defined for English Language Learners

spark plug

noun

Definition of spark plug for English Language Learners

  • : a part of an engine that produces a spark that makes the fuel burn


SPARK PLUG Defined for Kids

spark plug

noun

Definition of spark plug for Students

:a device used in an engine to produce a spark that ignites a fuel mixture


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