The Entente (Sometimes called the "Allies") and the Central Powers.
the allies and central powers.
In World War 1 Allied Powers, and in World War 2 Axis
World War 2 lasted from 1939 to 1945 and was the war in which the Allies defeated the Axis powers.
The allies defeated the central powers
The Central Powers lost to the Allies.
the allies
Axis and Allies
Great Britain, France and Russia were the main powers. They had other allies including the U.S., Japan, Spain and others.
The Allies suffered 6,657,950 more casualties than the Central Powers in World War I. Including killed, wounded, and missing. The Allies lost 22,062,427 soldiers while the Central Powers lost 15,404,477 soldiers.
The Axis did not exist in World War 1. Germany and its allies were called the Central Powers.
The opposite of allies (on your side) would be enemies. In World War I, the "Allies" were the Triple Entente and later the US and Italy, and were opposed by the Central Powers (Germany, Austria-Hungary, and the Ottoman Empire). In World War II, the major "Allied powers" were Britain, France, the USSR, and later the US, opposed by the Axis Powers (Germany, Italy, and Japan).