What constitutes a definition of fascism and fascist governments has been highly disputed regarding the exact nature of fascism and its core tenets amongst historians, political scientists, and other scholars ever since Benito Mussolini first used the term in 1914. In 2016 historian Ian Kershaw wrote that "trying to define 'fascism' is like trying to nail jelly to the wall".

A significant number of scholars agree that a "fascist regime" is foremost an authoritarian form of government; however, the general academic consensus also holds that not all authoritarian regimes are fascist, and more distinguishing traits are required for a regime to be characterized as such.; ; ; ; ; ; ;

Similarly, fascism as an ideology is also hard to define. Originally, it referred to a totalitarian political movement linked with corporatism which existed in Italy from 1922 to 1943 under the leadership of Benito Mussolini. Many scholars use the word "fascism" without capitalization in a more general sense to refer to an ideology (or group of ideologies) that has been influential in many countries at various times. For this purpose, they have sought to identify what Roger Griffin calls a "fascist minimum"—that is, the minimum conditions a movement must meet to be considered fascist. Other scholars, such as Robert Paxton, have denied that fascism is an ideology at all, characterizing it instead as a loose collection of "mobilizing passions".

The apocalyptic and millenarian aspects of fascism have often been subjected to study.; ; ; ; ;

By encyclopedias and dictionaries

American Heritage Dictionary of the English Language The American Heritage Dictionary of the English Language 5th edition (2022) defines fascism as "A system of government marked by centralization of authority under a dictator, a capitalist economy subject to stringent governmental controls, violent suppression of the opposition, and typically a policy of belligerent nationalism and racism". Its second definition is, "Oppressive, dictatorial control".

Cambridge Advanced Learner's Dictionary Cambridge Advanced Learner's Dictionary (4th edition, 2013) defines fascism as "a political system based on a very powerful leader, state control, and being extremely proud of country and race, and in which political opposition is not allowed."

Canadian Encyclopedia The Canadian Encyclopedia defines fascism as "military dictatorships and extreme right-wing governments and organizations (or individuals) known to be either violently anticommunist or violently anti-Semitic, or both. These are often important elements within fascism (as are the institutionalization of sexual repression and strong anti-female, anti-homosexual and pro-family biases), but the term should be more precisely confined to those mass movements and political parties that originated in the capitalist economies of Europe in the late 19th and early 20th centuries, culminating in Mussolini's Italy, Hitler's Germany and Salazar's Portugal. It is characterized by a hatred for liberalism, socialism, democracy, internationalism and the parliamentary system; by extreme patriotism and aggressive nationalism, and hostility to other nations and races; by a glorification of power, violence and war; by dreams of conquest and expansion; by a hankering after a supposedly glorious past; by paramilitary associations; by the myth of the "leader" to whom superhuman qualities are attributed; and by the creation of a convenient scapegoat - usually Jews - for all social, national and economic ills."

Chambers 21st Century Dictionary Chambers 21st Century Dictionary defines fascism as "a political movement or system characterized mainly by a belief in the supremacy of the chosen national group over all others, and in which there is, typically, state control of all aspects of society, a supreme dictator, suppression of democratic bodies such as trade unions and emphasis on nationalism and militarism". After recognizing the word being used to reference specifically the "system in force in Italy from 1922 to 1943", its third definition is "any system or doctrine characterized by a belief in the supremacy of a particular way of viewing things, usually an idealization of what is considered perfect".

Collins dictionaries COBUILD Student's Dictionary Plus Grammar (1995) defines fascism as a "right-wing political philosophy that believes in the importance of having strong rules, state control, and the prevention of political opposition."

Collins Canadian Dictionary (2nd edition, 2016) defines fascism as a "right-wing political system characterized by state control and extreme nationalism."

Collins COBUILD English Dictionary for Advanced Learners (3rd edition, 2001) defines lowercase f fascism and capital F Fascism as "a set of right-wing political beliefs that includes strong control of society and the economy by the state, a powerful role for the armed forces, and the stopping of political opposition."

Collins English Dictionary's website includes the following additional definitions such as:

"any ideology or movement inspired by Italian Fascism, such as German National Socialism; any right-wing nationalist ideology or movement with an authoritarian and hierarchical structure that is fundamentally opposed to democracy and liberalism." "any ideology, movement, programme, tendency, etc that may be characterized as excessively prescriptive or authoritarian." "the political movement, doctrine, system, or regime of Benito Mussolini in Italy, which encouraged militarism and nationalism, organizing the country along hierarchical authoritarian lines." "a governmental system led by a dictator having complete power, forcibly suppressing opposition and criticism, regimenting all industry, commerce, etc., and emphasizing an aggressive nationalism and often racism.

Collins English School Dictionary (1st edition, 2022) defines fascism as "an extreme political ideology or system of government with a powerful dictator and state control of most activities. Nationalism is encouraged and political opposition is not allowed."

Encarta Webster's College Dictionary The collegiate edition of the Encarta Webster's Dictionary defines fascism as "any movement, tendency, or ideology that favors dictatorial government, centralized control of private enterprise, repression of all opposition, and extreme nationalism".

Encyclopaedia Britannica The Encyclopedia Britannica defines fascism as a "political ideology and mass movement that dominated many parts of central, southern, and eastern Europe between 1919 and 1945 and that also had adherents in western Europe, the United States, South Africa, Japan, Latin America, and the Middle East", adding that, "Although fascist parties and movements differed significantly from one another, they had many characteristics in common, including extreme militaristic nationalism, contempt for electoral democracy and political and cultural liberalism, a belief in natural social hierarchy and the rule of elites, and the desire to create a (German: "people's community"), in which individual interests would be subordinated to the good of the nation."

Encyclopedia of European Social History In the Encyclopedia of European Social History, Alexander De Grand describes Italian and German Fascism as a "mass movement of the middle class" who, along with the ruling elite, had little to gain from the political and social upheaval of working-class socialist revolution. Fascism saw contemporary liberalism and liberal democracy as unable to continue control of what they saw as a disintegrating status quo. De Grand writes, "Faced with a shattered political order, a highly politicized and fragmented body politic, a revolutionary threat, and a profound loss of faith in the market mechanisms, Fascism put forward a vision of social and political solidarity based on the primacy of membership in the organic nation (Fascism) or race (Nazism)". The characteristics of Fascism included "the cult of the single leader who represented the essence of the nation or race; the single party through which all political life was directed; state control of mass communications and propaganda; the absorption of all independent social, leisure time, and professional activity within the state; the destruction of independent labor organizations; state direction of the economy within the context of private ownership; and the mobilization of society for war against domestic and foreign enemies". Additionally, according to De Grand, Fascism (and Nazism) aimed at "restoring traditional social and gender hierarchies"; to both "respect private property and ownership of the means of production" and, contradictorily, direct the economy at the level of the state; focused on militarism; and promoted a "spartan ethic of self-denial, austerity, and subordination of the individual to the group" (despite this not being reflected in the private behaviour of the leaders). Economically, the closeness between the state and industry led to "state-directed autarky with major branches of the economy organized into government-sponsored cartels geared to war production and to the exploitation of conquered territories".

Holocaust Encyclopedia The Holocaust Encyclopedia defines fascism as "a far-right political philosophy, or theory of government, that emerged in the early twentieth century. Fascism prioritizes the nation over the individual, who exists to serve the nation", and as "an ultranationalist, authoritarian political philosophy. It combines elements of nationalism, militarism, economic self-sufficiency, and totalitarianism. It opposes communism, socialism, pluralism, individual rights and equality, and democratic government".

When imbued explicitly and pre-dominantly with racist appeals to an implied racial empire, as in the case of Nazism, fascism takes on the tones of the Third Reich as opposed to the fascism of Mussolini's Italy or Franco's Spain, where racism may have been a notable element in the tone and substance of their messaging, but where the racial notions incentivizing the drive to Empire were somewhat less pronounced than in Germany. The Holocaust Encyclopedia distinguishes the Nazi style of Fascism as a fully realized fascism or as 'fascism in action' or otherwise as 'German fascism'--a form of fascism that has a different quality than the other discriminatory and ultranationalist fascisms at the time.

It exceeds the imprimatur of the Holocaust Encyclopedia to delineate this style of politics as anything other than 'Nazism,' and a reason for that may be that there are no other fully (and catastrophically) realized exemplars of this form of the Third Reich's mode of industrialized negative eugenic genocide as the methodological hallmark of an achieved global empire. However, a generic term to distinguish this style of politics—hovering somewhere between fascism and totalitarianism, with an extra-emphasis on the component of racism as a unifying factor within the system—is 'palingenetic ultranationalism' coined by Roger Griffin to describe a new consensus amongst scholars of fascism on this dimension, whose work has its own section amongst the scholars below.Roger Griffin (1993). The Nature of Fascism. London: Routledge, 1994.

Longman Dictionary of Contemporary English Longman Dictionary of Contemporary English (5th edition) defines fascism as "a right-wing political system in which people’s lives are completely controlled by the state and no political opposition is allowed."

Macmillan English Dictionary for Advanced Learners Macmillan English Dictionary for Advanced Learners of American English (2002) defines fascism as "a very right-wing political system in which the government is very powerful and controls society and the economy completely, not allowing any opposition, as was practiced in Italy and Germany in the 1930s and 40s."

Macquarie Dictionary