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English definition of “jack”

jack

noun [C] uk   /dʒæk/ us  

jack noun [C] (EQUIPMENT)

a piece of equipment that can be opened slowly under a heavy object such as a car in order to raise it off the ground: You need a car jack in order to change a wheel.Machinery and machinesHousehold equipment and domestic chores

jack noun [C] (CARD)

(also knave) a playing card with a picture of a man on it. It has a lower value than the cards showing a king or queen: the jack of clubsPlaying cards

jack noun [C] (BALL)

a small ball towards which other balls are rolled or thrown in the games of bowls or boulesBowls, bowling and croquet

jack noun [C] (ELECTRICAL)

a connection between two pieces of electrical equipmentElectrical switches and connections
(Definition of jack from the Cambridge Advanced Learners Dictionary & Thesaurus © Cambridge University Press)
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