Why was the side against Germany/Japan/Italy called the Allies?

by Talosian_Prav

Was there any rhyme or reason for calling one side the "Allies" and the other side the "Axis Powers" during World War II? Because you could easily say that Germany, Japan, and Italy formed an alliance as well. What was stopping them from calling themselves the Allies? Is it just because they lost the war?

Corohr

To piggyback on this question.

What did the Axis powers call the Allies? Were they called the Allies or something else?