Pronunciation: (al'īz, u-līz'),[key] —n. 1. pl. of ally. 2. (cap.) (in World War I) the powers of the Triple Entente (Great Britain, France, Russia), with the nations allied with them (Belgium, Serbia, Japan, Italy, etc., not including the United States), or, loosely, with all the nations (including the United States) allied or associated with them as opposed to the Central Powers.
3. (cap.) the 26 nations that fought against the Axis in World War II and, with subsequent additions, signed the charter of the United Nations in San Francisco in 1945.
4. (cap.) the member nations of NATO.