hijack (v.)

by 1922 (perhaps c. 1918), American English, of unknown origin; perhaps from high(way) + jacker "one who holds up" (agent noun from jack (v.)). In early use "to rob (a bootlegger, smuggler, etc.) in transit;" sense of "seize an aircraft in flight" is 1968 (also in 1961 variant skyjack), extended 1970s to any form of public transportation. Related: Hijacked; hijacking. Related: Hijacker.

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Definitions of hijack from WordNet
hijack (v.)
take arbitrarily or by force;
Synonyms: commandeer / highjack / pirate
hijack (v.)
seize control of;
they hijacked the judicial process
hijack (n.)
seizure of a vehicle in transit either to rob it or divert it to an alternate destination;
Synonyms: highjack