Word forms: (regular plural) jacks
(Automotive engineering: Vehicle components, Bodywork, controls, and accessories) A jack is a device for lifting a vehicle off the ground. ⇒ There was a truck there with a jack under the back wheel. ⇒ The car has built-in hydraulic jacks, which facilitate rapid tire changes. ⇒ Always keep a tire iron, spare tire, and car jack in the trunk of the car, in case of punctures.
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