What describes a substance made of more than one element?

The correct answer is a compound. A substance made of more than one element that is chemically bonded together is known as a compound. Compounds have distinct properties that differ from the individual elements they are composed of. For example, water (H₂O) is a compound made from hydrogen and oxygen, and it exhibits characteristics that are different from both gases.

In the context of materials and their combinations, composites and mixtures are often discussed. A composite refers to a material made by combining two or more different materials to produce superior properties, often retaining some of the original properties of the materials used. A mixture, on the other hand, is a physical combination of two or more substances where each substance retains its own properties and can be separated by physical means.

Alloys are specific types of mixtures made from metals, where two or more elements (at least one of which is a metal) are combined in a way that enhances their properties, such as strength or resistance to corrosion. While alloys may include multiple elements, the term "alloy" specifically refers to metallic combinations rather than the broader classification of compounds.

Therefore, the precise term for a substance made of more than one element in a chemical context is best identified as a compound.