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

In the case of Iran that would entail deploying 1.9 million people — almost all the U.S. military’s active duty, reserve and National Guard personnel.

From Los Angeles Times • Mar. 3, 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

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

Ross served in the Indiana National Guard and was deployed to active duty.

From The Wall Street Journal • Jan. 9, 2026

That April he was taken off high-pressure code breaking and discharged from active duty in the Army.

From "The Woman All Spies Fear" by Amy Butler Greenfield