elopement
[ ih-lohp-muh nt ]
/ ɪˈloʊp mənt /
noun
an act or instance of running off secretly, as to be married.
an act or instance of leaving a safe area or safe premises, done by a person with a mental disorder or cognitive impairment: Parents of autistic children need strategies to cope with elopement.
See also wandering(def 6).