[n] a war in which the major nations of the world are involved
[n] a war between the Allies (Russia France British-Empire Italy US Japan Rumania Serbia Belgium Greece Portugal Montenegro) and the Central Powers (Germany Austria-Hungary Turkey Bulgaria) from 1914 to 1918
[n] a war between the Allies (Australia Belgium Bolivia Brazil Canada China Colombia Costa-Rico Cuba Czechoslovakia Dominican-Republic El-Salvador Ethiopia Greece Guatemala Haiti Honduras India Iran Iraq Luxembourg Mexico Netherlands New-Zealand Nicaragua Norway Panama Philippines Poland South-Africa United-Kingdom US USSR Yugoslavia) and the Axis (Albania Bulgaria Finland Germany Hungary Italy Japan Rumania Slovakia Thailand) from 1939 to 1945