Although the doctors had been able to 'keep her illness at bay' [=to prevent her illness from becoming worse] for a few months, the disease soon began to spread again.
Armed with a gun, he 'held the police at bay' [=he did not allow the police to arrest him] for 10 hours.
The soldiers 'kept the attackers at bay'. [=they did not allow the attackers to come closer]
(..) We judge because the souls of history hang in the balance. Because our faith has never failed us. Our faith keeps the darkness of hell at bay. Then use your faith to help me find my little girl. Only the demon knows where she is. Then tell me, where do I find this demon? (..)2006 Silent Hill