warn
verbUK /wɔːn/
US /wɔːrn/
To tell someone about danger so they can be safe.
The lifeguard warned the swimmers about the strong waves.
OTHER MEANINGS
2. To tell someone about a possible problem or trouble.
The teacher warned us that the test would be hard.
3. To give advice about what to do or not do.
The doctor warned him not to eat too much sugar.
4. To tell someone to stop doing something or they will be punished.
The referee warned the player about his rough tackling.