| dissident | a person who disagrees with and criticises their government, especially because it is undemocratic |
| diversionary | describes an action to distract the enemy from the main point of attack |
| dogfighting | an aerial battle between opposing fighter planes |
| dominion | a nation that was part of the British Empire but had its own government e.g. Australia from 1901 to 1953 |
| dysentery | an infection of the intestine with bacteria or protozoa, characterised by severe diarrhoea |
| egalitarian | supporting the idea that all people are equal and should have the same rights and opportunities |
| embark | to load goods or passengers onto a ship or aeroplane |
| enact | to make a proposal into a law |
| encampment | a group of tents in a particular place, especially those used by soldiers |
| enlist in | to join a country's military force, such as the army - enlisted in, enlisting in; also enlistment (noun) |
| enteric fever | another name for typhoid fever, an infection caused by ingestion of Salmonella typhosa bacteria with food or water |
| escort | one or more guards, soldiers, vehicles or vessels who accompany others for protection, guidance or restraint, or as a symbol of honour |
| eugenics | the study of methods to improve the human race by selecting parents who will produce children with desirable traits |
| euthanise | to kill a person or animal painlessly, such as to relieve suffering from an incurable illness |
| expeditionary | relating to a journey undertaken for an exploratory or military purpose |
| extortionist | a person who gets something from someone by using force or threats |
| famine | a situation when large numbers of people experience extreme hunger due to drought, overpopulation or civil war, and many of them die |
| feint | a mock attack or military movement designed to distract an adversary |
| flagship | the most important ship in a fleet, on which the commander of the fleet sails |
| flamethrower | a weapon that sprays a stream of burning fuel, such as gasoline or napalm |
| Flanders | a World War I battle area in Belgium's East and West Flanders, the Netherlands' Zeeland and France's Nord |
| fleet | a group of ships organised to act together, such as fight a battle |
| foot pad | an unmade minor walking trail formed only by foot traffic |
| fragmentation | describes a weapon designed to explode into many small pieces, especially an anti-personnel weapon |
| front | a line where two opposing military forces are facing each other |
| gallantry | bravery shown by a person who is facing danger, for example when a soldier is fighting in a war |
| gangrene | the decay in a part of a person's body if the blood stops flowing to it, as a result of illness or injury |
| garrison | a group of soldiers who guard the town or building where they live |
| genocide | the deliberate killing of a national, racial, political or cultural group of people or a policy intended to destroy them |
| Great Britain | refers to the island of England, Wales and Scotland, and its surrounding isles, but not Northern Ireland - 'Britain' for short |
| Great War | the term used to describe World War I by the generation that lived through it - also 'First World War' |
| green line | a line of demarcation between two enemies in a conflict |
| grenade | a small bomb that can be thrown by hand |
| gross domestic product (GDP) | the total value of goods and services produced by a nation in a year |
| guerrilla | person who fights as part of an unofficial army, usually against an official army or police force |
| hardtack | a hard, flat, saltless biscuit that formed part of navy or army rations |
| heave to | to stop moving forward, especially a ship or vessel |
| heliograph | an instrument with mirrors and a shutter used for sending messages in Morse code by reflecting the sun's rays |
| home front | the country where civilians live |
| howitzer | a large gun with a short barrel that fires shells high up into the air so that they drop down onto a target |
| humanitarian | relates to the promotion of human welfare, dignity and respect |
| illiterate | unable to read or write |
| in perpetuity | describes as action or activity that's intended to last forever |
| incendiary | describes a weapon designed to cause a small fire; dropped together from aircraft to cause widespread damage |
| indemnity | an amount of money paid to someone because of some damage or loss they have suffered |
| infantry | soldiers who fight on foot |
| insurgent | person who fights against the army or government of their own country |
| internee | a person put in prison for political reasons, especially an enemy citizen during wartime or a terrorism suspect |
| internment | the practice of putting people, usually civilians, in prison for political reasons, especially enemy foreign nationals during wartime or terrorism suspects |
| jaunty | naval slang for the master-at-arms, a senior sailor responsible for good order and discipline |