Index and indice (a French word that can be translated in English with 'clue', 'hint', or even otherwise) are two semiotic typologies that cover a largely overlapping range, but should not be confused. Indeed, in one case, an individual binary relationship between two entities is involved; in the other one, a material object works as a trigger for an inference that allows one to retrieve information about a state of the world not otherwise accessible. If this definition is valid, a "classical" notion of reference (implying an "external" world at least partially independent of signs - linguistic or not - that refer to it) is more important for the indice than for the index. In addition, an element of mental causation is required mostly for indice: the material object that triggers inference and interpretation is compulsive toward the interpreting mind. (Namely, that is the case for Prieto’s theory).Focusing on the role of words can help to a better grasping of the difference between the two categories concerned. For instance, Peirce's exquisite analysis of the semantic dynamics relating to proper names (whose indexicality is "enriched", over time, by iconic and symbolic elements) brings into play certain dimensions that have nothing to do with the way indice works, which is exhausted every time in single apperception (at which point the dimension of the code - splitted in noetic and sematic field by Prieto - comes into play).