Carjacking is the crime of stopping a car and using a weapon, or a serious threat, to make the driver give you the car or drive you somewhere. News writers use it as a noun: a carjacking in the car park. It is also the -ing form of the verb carjack. The word came from American English and then into British news. Though actually, older speakers may never use it at all; they may just say someone stole a car at knifepoint. The new blend is handy for headlines, but the ugly fact it names is older than the word. It still points to a driver who is there, not to a quiet theft of an empty car.