World War I Definition

noun
The war (1914-18) between the Allies (Great Britain, France, Russia, the U.S., Italy, Japan, etc.) and the Central Powers (Germany, Austria-Hungary, etc.)
Webster's New World
Synonyms:
pronoun

The war from 1914 to 1918 between the Entente Powers of the British Empire, Russian Empire, France, Italy, the United States and other allied nations, against the Central Powers represented by the German Empire, Austria-Hungary, the Ottoman Empire, and Bulgaria.

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