head of state

[Glennaunsar]

the chief public representative of a country who may also be the head of government

[Ernesto]

A head of state (or chief of state) is the public persona who officially embodies a state in its unity and legitimacy. Depending on the countrys form of government and separation of powers, the head of state may be a ceremonial figurehead or concurrently the head of government and more (such as the president of the United States, who is also commander-in-chief of the United States Armed Forces).
In a parliamentary system, such as the United Kingdom or India, the head of state usually has mostly ceremonial powers, with a separate head of government. However, in some parliamentary systems, like South Africa, there is an executive president that is both head of state and head of government. Likewise, in some parliamentary systems the head of state is not the head of government, but still has significant powers, for example Morocco. In contrast, a semi-presidential system, such as France, has both heads of state and government as the de facto leaders of the nation (in practice they divide the leadership of the nation between themselves). Meanwhile, in presidential systems, the head of state is also the head of government. In one-party ruling communist states, the position of president has no tangible powers by itself, however, since such a head of state, as a matter of custom, simultaneously holds the post of General Secretary of the Communist Party, they are the executive leader with their powers deriving from their status of being the party leader, rather than the office of president.
Former French president Charles de Gaulle, while developing the current Constitution of France (1958), said that the head of state should embody lesprit de la nation (the spirit of the nation).

[Williebit]

Head of State, or Chief of State, is a term used in constitutional law, international law, political science, and diplomatic protocol when referring to the official who holds the highest ranked position in a sovereign state and has the vested or implied powers to act as the chief public representative of a state. Heads of state in most countries are natural persons holding an office; however, in four United Nations member states the head of state position is held by a body of persons: the Federal Council of Switzerland, the Presidency of Bosnia and Herzegovina, the Co-Princes of Andorra and the Captains Regent of San Marino.
The term head of state is often used differentiating it from the term head of government, e.g. as in article 7 of the Vienna Convention on the Law of Treaties, article 1 of the Convention on the Prevention and Punishment of Crimes against Internationally Protected Persons, including Diplomatic Agents and the United Nations protocol list. For instance, in parliamentary systems like the United Kingdom of Great Britain and Northern Ireland and the Federal Republic of Germany; the Monarch and the President are recognized as their respective heads of state, while the Prime Minister and the Chancellor are recognized as the heads of government. However in republics with a presidential system, as in the United States and the Federative Republic of Brazil, their presidents are recognized as being both heads of state and heads of government. The latter is also generally true in absolute monarchies and sometimes as well in other forms of authoritarian government.