* To describe a person who is always on the lookout for danger or problems. For example, you might say that a security guard is vigilant in their duties, or that a parent is vigilant about their child's safety.
* To describe a situation in which there is a high level of alertness or awareness. For example, you might say that the city was vigilant after a series of terrorist attacks, or that the company was vigilant about its cybersecurity measures.
* To describe something that is designed to detect danger or problems. For example, you might say that a security camera is vigilant, or that a smoke alarm is vigilant.
Here are some examples of how you can use the word "vigilant" in a sentence:
* The security guard was vigilant in his duties, and he quickly spotted the suspicious man.
* The city was vigilant after a series of terrorist attacks, and there was a heavy police presence on the streets.
* The company was vigilant about its cybersecurity measures, and it had a strong firewall in place.
* The smoke alarm was vigilant, and it sounded the alarm as soon as the fire started.