Metonymy is a linguistic and conceptual structure where one element stands referentially for another.  Metonymy can be used for a range of ideological purposes.  For example, instrument-for-agent or place-for-person metonymies allow responsibility for an action or process to be glossed over or 'mystified'.  Part-for-whole metonymies allow certain elements of an individual's identity to be profiled or for one subtype of a category to stand stereotypically for all its members.