| A | B |
| Armistice | Temporary suspension of hostilities by agreement between the opponents; truce. |
| Morale | The confidence, enthusiasm, and discipline of a person or group at a particular time. |
| Total War | A war where every resource, including all civilian and military personal, are used to gain victory. |
| Trench Warfare | A form of fighting whereby two sides fight each other from opposite trenches. |
| Great War | WWI |
| Triple Entente | Pre-WWI alliance between Russia, Great Britain, and France. |
| Genocide | The deliberate killing of a large group of people, especially those of a particular ethnic group, race, or nationality. |
| Shell Shock | Medical condition caused by prolonged exposure to the distressing experiences of trench warfare. |
| Czar | Emperor of Russia before 1917. |
| Western Front | The line of trenches stretching 440 miles from the Swiss border to the North Sea. This line moved very little between 1914-1918, despite attempts on both sides to break through. |
| Stalemate | The deadlock on the Western Front during WWI when there was little movement or gain of land. |
| War to End All Wars | WWI |
| Kaiser | German Emperor |
| Reparations | The payment of damages in money or materials paid by a defeated nation to the winning nation as a result of the war. |
| Annexation | The formal act of acquiring territory by conquest or occupation. |
| Propaganda | Ideas, facts, or allegations spread deliberately to further one's cause or damage an opposing cause. |
| Neutrality | The state of not taking sides, especially in a war or a dispute. |
| Allies | Great Britain, France, Russia, Belgium, Italy, Japan, Portugal, US |
| Triple Alliance | Pre-WWI alliance between Germany, Italy, Austria-Hungary |
| Treaty of Versailles | Peace settlement that ended WWI |
| Mobilization | The act of assembling and making both troops and supplies ready for war. |
| Lusitania | British passenger liner sunk off the coast of Ireland by German U-boats in 1915. |
| Central Powers | Germany, Austria-Hungary, The Ottoman Empire, Bulgaria (1915) |
| U-Boats | German submarines |
| Militarism | Belief that a country should maintain a strong military capability and be prepared to use it aggressively. |
| Eastern Front | Fighting on the German-Russian, Austro-Romanian fronts |
| Isolationism | A policy of remaining apart from the affairs or interests of other groups, especially the political affairs of other countries. |
| Nationalism | Extreme pride in one's country |
| Sussex Pledge | Promise made in 1916 by Germany to the US prior to the US's entry into the war regarding the German's naval warfare. |