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English definition of “jackknife”


verb [I]     /ˈdʒæk.naɪf/
If a truck that has two parts jackknifes, one part moves around so far towards the other part that it cannot be driven: The oil tanker jackknifed after skidding on the ice.Accidents involving vehicles
(Definition of jackknife verb from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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