Lost

absent, adrift, astray, at sea, cast away, disappeared, disoriented, down the drain*, fallen between cracks, forfeit, forfeited, gone, gone astray, hidden, invisible, irrecoverable, irretrievable, irrevocable, kiss goodbye, lacking, minus, mislaid, misplaced, missed, nowhere to be found, obscured, off-course, out the window, strayed, unredeemed, vanished, wandering, wayward, without