active duty

American  

noun

Military.

1. the status of full-time service.

   on active duty.

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active duty Idioms  

1. Full-time service, as in Julian is 81, but he still comes to the office every day and is very much on active duty. This term comes from the military, where it stands in opposition to reserve, which refers to troops still in the military but not actively engaged. It is occasionally transferred to civilian matters as well. [First half of 1800s]

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Example Sentences

LONDON—In 2001, Prince Andrew retired from active duty in the Royal Navy, with a reputation as a war hero and something of a playboy.

From The Wall Street Journal • Feb. 21, 2026

Kelly could even be recalled to active duty, then court-martialed, an act that would remove his military status entirely and even land the senator in prison.

From Slate • Jan. 13, 2026

The players only play for the love of the game, graduate, then go on to active duty in the armed forces for a minimum of five years.

From Los Angeles Times • Jan. 10, 2026

Closer to the front line, many men on active duty are also shelving the idea of starting a a relationship.

From BBC • Jan. 9, 2026

And then he said, “They will not act as segregationists or integrationists, but as soldiers called to active duty to carry out their assigned tasks.”

From "Warriors Don't Cry: A Searing Memoir of the Battle to Integrate Little Rock's Central High" by Melba Pattillo Beals