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

From BBC • May 2, 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

The Revolutionary Guard has an estimated 190,000 active duty personnel, or nearly 10 times the size of Hezbollah’s force before the 2024 Israeli offensive.

From The Wall Street Journal • Feb. 28, 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

Released from active duty, Fezzik followed the wall around to a quiet place and waited.

From "The Princess Bride" by William Goldman