To observe and protect a military unit or area from a position where covering fire can be provided.MILITARY Two armored vehicles overwatched the infantry's advance.
To maintain protective or supervisory observation of someone or something.RARE A lone sentry overwatched the camp throughout the night.
To exhaust someone, especially oneself, through prolonged watching or wakefulness.OBSOLETE He had overwatched himself during his long vigil beside the sickbed.