A.W.O.L.

adj

missing, not present when needed. The expression has been extended, especially by British middle-class speakers, from its original meaning in army jargon of 'absent without leave' to inexplicably absent, either with the implication of fleeing to avoid responsibilities, or wan-dering uncontrolled or running amok.

► 'Ollie's gone awol again; he disappeared with a bottle and no one's seen him for days.' (Recorded, upper-class youth, London, 1985)