The substance known as the universal solvent is water. Water's unique molecular structure enables it to dissolve a wide variety of substances, making it essential for many chemical reactions and biological processes. This property is primarily due to water's polarity, which allows it to interact with other polar molecules and ions. Because of its solvent abilities, water plays a crucial role in various biological functions, including nutrient transport, waste removal, and cellular processes. Its role as a universal solvent also extends to industrial and environmental applications, where it helps in the mixing and transportation of various compounds.