say it: HAHY-jak-ur
hijacker is a noun meaning "a holdup man who stops a vehicle and steals from it". It carries 2 recorded senses.
a holdup man who stops a vehicle and steals from it
someone who uses force to take over a vehicle (especially an airplane) in order to reach an alternative destination
airplane
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for hijacker come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.