Meaning of “caution” - Learner’s Dictionary

caution

verb uk us /ˈkɔːʃən/
WARN [ I, T ] formal

to warn someone of something:

[ often passive ] They were cautioned against buying shares in the company.
POLICE [ T ] UK

If a police officer cautions someone, they give that person a warning that they will be punished next time.

(Definition of “caution verb” from the Cambridge Learner’s Dictionary © Cambridge University Press)