In this paper I will attempt to elaborate what I would like to call a phenomenology of ideology. Why a phenomenology? Because the expression "ideology" suffers from both misuse and abuse when it occurs in a polemical framework. Only a rigorous semantics controlled by an accurate description of the situations in which this expression is relevant could put an end to this abuse; such would be the approach which I call phenomenology. (I could also say a semantical phenomenology, but it is enough to say phenomenology, since the delineation of such a phenomenon has necessarily a linguistic dimension.)