The use (and sometimes abuse) of the word populism in political language seems to be a common practice. It is one of the most discussed terms related to democratic regimes nowadays. At the same time however, it remains a vague notion that admits different kind of interpretations. Nevertheless, it is possible to find a meaning for this term able to associate the different political experiences identified with that name. Populism may be understood as a political worldview based on a specific set of key ideas, adaptable for different periods and places. The main purpose of this article is to analyze each of the basic concepts that constitute the ideological meaning of populism in order to deal with some of the analytical challenges implicit in it. The central hypothesis of this work is that the populist worldview is founded on a potentially antidemocratic core, or, in other words, a core which that is incompatible with the modern ideal of democracy.