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English definition of “jack”

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jack

noun [C]  /dʒæk/ us  

jack noun [C] (DEVICE)

a device used to raise and hold something heavy off the ground, esp. one for raising a vehicle so that a tire can be changed

jack noun [C] (CARD)

a playing card that has a picture of a man on it and has a lower value than the cards showing a king or queen: the jack of diamonds

jack noun [C] (ELECTRICITY)

a hole into which a wire connected to a piece of electrical equipment can be plugged so that the equipment can operate: a microphone jack
(Definition of jack from the Cambridge Academic Content Dictionary © Cambridge University Press)
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