<p><strong>Noun</strong></p><ul><li>alertness and prudence in a hazardous situation; care; wariness: Landslides ahead—proceed with caution</li><li>Synonyms: watchfulness, vigilance, heed, discretion, circumspection</li><li>Antonyms: carelessness</li><li>a warning against danger or evil; anything serving as a warning: By way of caution, he told me the difficulties I would face</li><li>Synonyms: counsel, advice, admonition</li><li>Informal: a person or thing that astonishes or causes mild apprehension: She's a caution. The way he challenges your remarks is a caution.</li></ul><p><strong>Verb (used with object)</strong></p><ul><li>to give warning to; advise or urge to take heed</li><li>Synonyms: forewarn, admonish</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>to warn or advise: The newspapers caution against overoptimism</li></ul>