War Department

American  

noun

U.S. History.

1. the department of the federal government that, from 1789 until 1947, was responsible for defense and the military establishment: in 1947 it became the Department of the Army, which became part of the Department of Defense when it was established in 1949.

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Example Sentences

When asked to comment, Pentagon spokesman Sean Parnell said in a statement: “It is the duty of the War Department to ensure that the commander-in-chief has every possible military option at his disposal.”

From The Wall Street Journal • Apr. 4, 2026

“The president has made it clear that you will not have a nuclear weapon. The War Department agrees,” Hegseth said.

From Los Angeles Times • Mar. 24, 2026

The Department of Defense, now called the War Department, is investing directly in companies, demanding greater production and new technology.

From Barron's • Jan. 14, 2026

He reverses a post-World War II decision that renamed the War Department the Department of Defense, returning its meaning to “war.”

From Salon • Nov. 8, 2025

By this time, Lincoln is overdue at the War Department.

From "Lincoln's Last Days: The Shocking Assassination that Changed America Forever" by Bill O'Reilly