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

The US has a significant military presence in Germany, with more than 36,000 active duty troops assigned to bases across the country as of last December.

From BBC • Apr. 29, 2026

Reduced and free admission will be available to those receiving federal food assistance and active duty personnel.

From The Wall Street Journal • Apr. 16, 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

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