warn
/wɔːn वॉन्/ verb [T] 1 warn somebody (of something) ; warn somebody (about somebody/something) to tell somebody about something unpleasant or dangerous that exists or might happen, so that he/she can avoid it (किसी व्यक्ति को) आसन्न, विद्यमान प्रतिकूलता या ख़तरे की पूर्वसूचना देना, (से) सचेत करना (ताकि वह अपना बचाव कर सके)
When I saw the car coming I tried to warn him, but it was too late.
The government is warning the public of possible terrorist attacks.