Final answer:
Haute Couture refers to high-end, custom-made fashion that is trendsetting and very expensive, characterized by exclusive designs, handwork, and luxury materials.
Step-by-step explanation:
The term that refers to high-end, trendsetting fashion that is usually very expensive is Haute Couture. This type of fashion is distinguished by custom-made, exclusive clothing designed by fashion houses for individual clients, often involving meticulous handwork and premium materials. The description provided of a woman dressed in luxurious attire with a white satin dress and a cashmere shawl, adorned with gold jewelry and using expensive scented oil for her hair, is an example that closely aligns with the affluence and exclusivity associated with Haute Couture fashion. Unlike Pret-a-Porter (ready-to-wear), Fast Fashion, or even Avant-Garde Fashion which can be innovative but not necessarily high-end, Haute Couture represents the pinnacle of personalized luxury in the fashion industry.