As a political philosopher by training, and now political scientist by appointment, I have long been privately embarrassed that I am not sure how to define “state,” “government,” “regime,” and “nation.” On reflection, these words are used differently in various academic contexts. To make things more complicated, the discussion is international, and we are often dealing with translations of words that don’t quite match up across languages.

For instance, probably the most famous definition of “the state” is from Max Weber’s Politics as Vocation (1919). He writes:

Staat ist diejenige menschliche Gemeinschaft, welche innerhalb eines bestimmten Gebietes – dies: das „Gebiet“, gehört zum Merkmal – das Monopol legitimer physischer Gewaltsamkeit für sich (mit Erfolg) beansprucht.

[The] state is the sole human community that, within a certain territory–thus: territory is intrinsic to the concept–claims a monopoly of legitimate physical violence for itself (successfully).

Everyone translates the keyword here as “state,” not “government.” But this is a good example of how words do not precisely match across languages. The English word “government” typically means the apparatus that governs a society. The German word commonly translated as “government” (“der Regierung“) means an administration, such as “Die Regierung von Joe Biden” or a Tory Government in the UK. (In fact, later in the same essay, Weber uses the word Regierung that way while discussing the “typical figure of the ‘grand vizier'” in the Middle East.) Since “government” has a wider range of meanings in English, it wouldn’t be wrong to use it to translate Weber’s Staat.

Another complication is Weber’s use of the word Gemeinschaft inside his definition of “the State.” This is a word with such specific associations that it is occasionally used in English in place of our vaguer word “community.” A population is not a Gemeinschaft, but a tight association can be. Thus to translate Weber’s phrase as “A state is a community …” is misleading.

For Americans, a “state” naturally means one of our fifty subnational units, but in Germany those are Länder (cognate with “lands”). The word “state” derives from the Latin status, which is as “vague a word as ratio, res, causa” (Paul Shorey, 1910) but can sometimes mean a constitution or system of government. Cognates of that Latin word end up as L’État, el Estado and similar terms that have a range of meanings, including the subnational units of Mexico and Brazil. In 1927, Mussolini said, “Tutto nello Stato, niente al di fuori dello Stato, nulla contro lo Stato (“Everything in the State, nothing outside the State, nothing against the State”). I think he basically meant that he was in charge of everything he could get his hands on. Louis XIV is supposed to have said “L’État c’est moi,” implying that he was the government (or the nation?), but that phrase may be apocryphal; an early documented use of L’État to mean the national government dates to 1799. In both cases, the word’s ambiguity is probably one reason it was chosen.

“Regime” can have a negative connotation in English, but political theorists typically use it to mean any government plus such closely related entities as the press and parties and prevailing political norms and traditions. Regimes can be legitimate, even excellent.

If these words are used inconsistently in different contexts, then we can define them for ourselves, as long as we are clear about our usage. I would tend to use the words as follows:

• A government: either the legislative, executive, and judicial authority of any entity that wields significant autonomous political power (whether it’s territorial or not), or else a specific group that controls that authority for a time. By this definition, a municipality, the European Union, and maybe even the World Bank may be a government.

(A definitional challenge is deciding what counts as “political” power. A company, a church, a college, an insurgent army, or a criminal syndicate can wield power and can use some combination of legislative, executive, and/or judicial processes to make its own decisions. Think of canon law in the Catholic Church or an HR appeals processes inside a corporation. Weber would say that the fundamental question is whether an entity’s power depends on its own monopolistic use of legitimate violence. For instance, kidnapping is a violent way to extract money, but it does not pretend to be legitimate and it does not monopolize violence. Taxation is a political power because not paying your taxes can ultimately land you, against your will, in a prison that presents itself as an instrument of justice. Not paying a private bill can also land you in jail, but that’s because the government chooses to enforce contracts. Your creditor is not a political entity; the police force is. However, when relationships between a government and private entities are close, or when legitimacy is controversial, or when–as is typical–governments overlap, these distinctions can be hard to maintain and defend.)

• A state: a government plus the entities that it directly controls, such as the military, police, or public schools. For example, it seems most natural to say that a US government controls the public schools, but not that a given school is part of the government. Instead, it is part of the state. Likewise, an army can be in tension with the government, yet both are components of the state.
• A regime: the state plus all non-state entities that are closely related to it, e.g., political parties, the political media, and sometimes the national clergy, powerful industries, etc. We can also talk about abstract characteristics, such as political culture and values, as components of a regime. A single state may change its regime, abruptly or gradually.
• A country: a territory (not necessarily contiguous) that has one sovereign state. It may have smaller components that also count as governments but not as countries.
• A nation: a category of people who are claimed (by the person who is using this word) to deserve a single state that reflects their common identity and interests. Individuals can be assigned to different nations by different speakers.
• A nation-state: a country with a single functioning and autonomous state whose citizens widely see themselves as constituting a single nation. Some countries are not nations, and vice-versa. People may disagree about whether a given country is a nation-state, depending on which people they perceive to form a nation.

See also: defining capitalism; avoiding a sharp distinction between the state and the private sphere; the regime that may be crumbling; what republic means, revisited etc.