Master the word "CAUTION" in English: definitions, translations, synonyms, pronunciations, examples, and grammar insights - all in one complete resource. Caution definition: alertness and prudence in a hazardous situation; care; wariness.. See examples of CAUTION used in a sentence. Definition of caution noun in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more. Caution is great care which you take in order to avoid possible danger. Extreme caution should be exercised when buying part-worn tyres. The Chancellor is a man of caution.