Pronunciation: (kô'shun),[key] —n. 1. alertness and prudence in a hazardous situation; care; wariness: Landslides ahead—proceed with caution. 2. a warning against danger or evil; anything serving as a warning: By way of caution, he told me the difficulties I would face. 3. Informal.a person or thing that astonishes or causes mild apprehension: She's a caution. The way he challenges your remarks is a caution.
—v.t. to give warning to; advise or urge to take heed.
—v.i. to warn or advise: The newspapers caution against overoptimism.