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

See Examples For:

active duty

The US military deployment in Germany is by far its biggest in Europe, currently at more than 36,000 active duty troops compared to about 12,000 troops in Italy and a further 10,000 in the UK.

From BBC ● May 22, 2026

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

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

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

He ordered the doctors to make Oppenheimer eligible for active duty.

From "Bomb" by Steve Sheinkin