What term refers to a chemical combination of two or more atoms?

The term that refers to a chemical combination of two or more atoms is "compound." A compound is formed when two or more different elements chemically bond together, creating a substance with unique properties that differ from those of the individual elements. For instance, water (H2O) is a compound made up of two hydrogen atoms and one oxygen atom bonded together.

In contrast, a molecule may refer to a group of two or more atoms bonded together, which can be a single element or a compound. An element is a pure substance consisting of only one type of atom, and a mixture involves physical combinations of substances where each retains its own properties. Therefore, "compound" is the most precise term for indicating a distinct chemical combination of different atoms.