In culinary terms, what does the term “mother sauce” refer to?

The term "mother sauce" refers to a fundamental sauce in classical French cuisine from which a variety of other sauces can be derived, known as derivative sauces. These mother sauces serve as the foundation for creating different variations by adding ingredients or modifying techniques, making them essential in culinary training. The primary mother sauces include béchamel, velouté, espagnole, tomato, and hollandaise, each having its own unique base yet offering a framework for countless other sauces. This concept highlights the versatility and creativity available within classical cooking methods, allowing chefs to innovate while relying on fundamental techniques.