1 [intransitive and transitive]
to warn someone that something might be dangerous, difficult etc
caution (somebody) against something
Business leaders are cautioning against hasty action that would hamper flexibility.
caution (somebody) that
Officials were quick to caution that these remarks did not mean an end to the peace process.
caution somebody to do something
He cautioned them to avoid the forest at night.
2 [transitive] British EnglishSCL
to warn someone officially that the next time they do something illegal they will be punished
caution somebody for (doing) something
She was cautioned for speeding.
to warn someone officially that what they say to a police officer may be used as evidence in a court of law