highjacker vs highjack

highjacker and highjack both are nouns.

Word	Noun	Adjective	Verb	Adverb
highjacker	Yes	No	No	No
highjack	Yes	No	Yes	No

highjacker (noun)	highjack (noun)
a holdup man who stops a vehicle and steals from it	seizure of a vehicle in transit either to rob it or divert it to an alternate destination
someone who uses force to take over a vehicle (especially an airplane) in order to reach an alternative destination

highjacker (verb)	highjack (verb)
	take arbitrarily or by force