Sometimes people surprise their doctors, nurses, and loved ones by recovering from an illness or injury despite a grim medical prognosis. When that happens, some people believe that miraculous healing has taken place.
Miraculous healing usually refers to when someone who had been sick or injured recovers in ways that can't be explained medically. It may also refer to a situation in which a sick or injured person recovers unexpectedly due to an extraordinary medical treatment that God may have used to heal the person, such as a transplant or a new medication that proved successful despite the odds against it working.
Usually, say believers, miraculous healing happens in response to prayer. If people have prayed for God to heal a person who then recovers, they often naturally connect their prayers with the healing that has taken place. But the cause of any miraculous healing must be taken on faith, since there's no way to objectively prove for certain what caused the unexpected healing, even if people understand all the various aspects of a person's medical treatment.