There are instead of saying that the word country, which is of French origin, has no definition clean or exclusive. The term is used as the most common synonym of nation State. The Larousse dictionary online provides several concepts to define it, insofar as it considers that a country is a nation, a region or territory.
On the other hand, a country is a certain geographical area and an entity politically independent, equipped with its own governance, its administration, its laws, its security forces and, of course, its people. However, a State may be composed of multiple countries or nations, such as the Spain (in the case of the Basque country and Catalonia, for example).
The word country sharing somehow the same meaning of the word nation (from the latin nātio), in particular concerning its sense of nation policy. In other words, it is the legal and political framework and the sovereignty of which is made a State.
Countries are divided by imaginary lines that determine their territory. These lines represent the boundaries, and these are they which delimit the space in which each State has jurisdiction.
When a country is under the domain of a distant country (i.e., is not able to decide its own governance or administration), it became a colony.
Then, we will retain that the countries are represented by their Governments in many international organizations, which can be scientific (as the European Space Agency, for example), economic (the common market of the South), police (Interpol) or political (UN, European Union, etc.).