on duty

Idioms  

1. At one's post, at work, as in The new nurse was on duty that evening, or The watchman was fired because he was drunk on duty. [Mid-1600s] The antonym, off duty, means “not engaged in one's work,” as in Captain Smith was much more amiable when he was off duty. [Mid-1800s]

---

Example Sentences

See Examples For:

on duty

Witnesses I spoke with were unanimous on one detail: “Only one of the three officers on duty that night tried to do anything.”

From Slate ● Aug. 11, 2026

But no one was on duty at the time, Altman said.

From Los Angeles Times ● Aug. 9, 2026

Speaking after the attack, Prime Minister Anutin Charnvirakul said he plans to introduce laws that restrict the carrying of firearms in public, with the new legislation only allowing government officials on duty to carry guns.

From BBC ● Aug. 7, 2026

"Some people are on duty and wouldn't have anything to eat so I still need to deliver food to them," the 50-year-old said.

From Barron's ● Jul. 11, 2026

It’s morning and a male nurse is on duty.

From "Without Refuge" by Jane Mitchell