Some key definitions concerning war and peace
[Gathered from the Oxford Advanced Learner's Dictionary, Wikipedia, TheFreeDictionary.com, Microsoft® Encarta®, Enzyklopädie Plus 2001 and Geneva Conventions]

Armistice: the effective end of a war, when the warring parties agree to stop fighting.

Cease-fire: a state of no-fire agreed to between opponents so they can discuss peace terms.

Civil war: a violent conflict in which the competing parties are segments of the same country or empire. Civil war is usually a high intensity stage in an unresolved political struggle for national control of state power. The conflict may be over matters such as religion, ethnicity, or distribution of wealth. Some civil wars are also categorized as revolutions when major societal restructuring is a possible outcome of the conflict.

Civilian: persons who take no part in hostilities, and who, while they reside in the zones, perform no work of a military character.

Combatant: A combatant is a soldier or guerrilla member who is waging war. Under the Geneva Conventions, persons waging war must have the following four characteristics:
(a) That of being commanded by a person responsible for his subordinates;
(b) That of having a fixed distinctive sign recognizable at a distance;
(c) That of carrying arms openly;
(d) That of conducting their operations in accordance with the laws and customs of war.
Combatants are even inhabitants of a non-occupied territory, who on the approach of the enemy spontaneously take up arms to resist the invading forces, without having had time to form themselves into regular armed units, provided they carry arms openly and respect the laws and customs of war.
Generally, prisoners not belonging to these categories are not protected by laws of war.

Developing country: There is no standard definition for the term “developing country”, which came into use in the early 1950s. However, a majority of the states concerned display common characteristic features, the most important of which are:
(a) insufficient food supply to large sections of the population
(b) low per capita income
(c) poor health status among large sections of the population
(d) inadequate educational opportunities
(e) high unemployment
(f) a widespread low standard of living, often combined with an extremely uneven distribution of existing goods and services.
The economies of most developing countries reveal a structure in which traditional modes of production – primarily in the agricultural sector – contrast with a dynamic, modern (usually industrial) sector. They are often characterised by a lack of capital for investment, mounting foreign trade and payments difficulties caused by heavy indebtedness, coupled with falling export revenues as well as a wide variety of other economic and social problems.
To date, there is no internationally binding list of developing countries. The United Nations, World Bank and the Development Assistance Committee (DAC) of the Organisation for Economic Cooperation and Development (OECD) apply similar criteria – chief among which is per capita income – but attach different weightings to those criteria. One result of this, for instance, is that the Eastern European countries and Israel are placed in different categories by the United Nations and the DAC.

Ethnic cleansing: translation of the Serbian/Croatian phrase etnicko cišcenje. The term refers to the expulsion of an "undesirable" population from a given territory, due to religious or ethnic discrimination, political, strategic or ideological considerations, or a combination of these.

Genocide: [gathered from the Convention on the Prevention and Punishment of Genocide, Art.II, as approved in 1948 by the United Nations General Assembly (full text)]
genocide means any of the following acts committed with intent to destroy, in whole or in part, a national, ethnical, racial or religious group, as such:
(a) Killing members of the group;
(b) Causing serious bodily or mental harm to members of the group;
(c) Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part;
(d) Imposing measures intended to prevent births within the group;
(e) Forcibly transferring children of the group to another group.

Guerrilla: The term was invented in Spain: it means "little war".
Guerrilla tactics are based on ambush and sabotage, and their ultimate objective is usually to destabilize an authority through long, low-intensity confrontation. It can be quite successful against an unpopular foreign regime: a guerrilla army may increase the cost of maintaining an occupation or a colonial presence above what the foreign power may wish to bear.
Guerrillas are often characterised as terrorists by their opponents.

Laws of war: The laws of war define the conduct and responsibilities of belligerent nations, neutral nations and individuals engaged in warfare, in relation to each other and to protected persons, usually meaning civilians. The laws of war are mandatory for nations bound by the appropriate treaties, primarily the Geneva conventions and Hague conventions, as well as customary unwritten rules of war.

Massacre: the killing of a large number of people.

Mass killing: the killing of a large number of people.

Mass punishment or collective penalty: punishment of a large group of people for only one person or a small group's wrongdoing. Following the 4th Convention of Geneva, art.33, "no protected person may be punished for an offence he or she has not personally committed. Collective penalties and likewise all measures of intimidation or of terrorism are prohibited."

Peace: originally, the state prevailing during the absence of war.
This conception of peace as a mere absence of overt violence, however, is still challenged by some as incomplete. As a matter of fact, the modern positive idea of peace is connected to justice, development and protection.
Peace, far to be just the absence of war, should be defined as the ensemble of conditions in which every subject can freely develop itself towards its own goals.

Poverty: discussed measure fixed at a per capita of $1 PPP (Purchasing Power Parity) in the low-income countries.

Prisoner of war: a combatant who has surrendered or been captured.

Terrorism: a tactic of violence that targets civilians, with the objective of forcing an enemy to favorable terms, by creating fear, demoralization, or political discord in the attacked population.

Third world: Third world is a term originally used to distinguish those nations that neither aligned with the capitalist West, the First world, nor with the Socialist East, the Second world. Many of these are located in Africa, Latin America, and Asia. They are often nations that were colonized by another nation in the past. The populations of third world countries are generally very poor but with high birth rates. In general they are not as industrialized or technologically advanced as the first world. The majority of the countries in the world fit this classification.

Truce: a state of no-fire agreed to between opponents so they can discuss peace terms.

War: originally, those conflicts where one or both belligerants have made a formal declaration.
This conception of war doesn't fit anymore to the modern world. Today we could call a war any large scale, violent conflict between two or more defined opponents.

War crime: every violation of the law of war.

Weapons of mass destruction: WMD encompasses a broad family of weapons, including conventional, biological, chemical, nuclear, or other advanced weapons. These weapons are characterized by their broad-sweeping intended effects, such as inflicting mass casualties and/or physical destruction.
Detecting, tracking, neutralizing, or minimizing the effects of such weapons have become key issues in support of the military services and government investigative agencies.

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