Melting Definition in Chemistry

Chemistry Glossary Definition of Melting

Ice cream in a bowl
An example of melting is seen when ice cream changes from a solid into a liquid. Chris Gramly/Getty Images

Melting is the process by which a substance changes from the solid phase to the liquid phase. Melting is also known as fusion, although this term has several meanings. Melting occurs when the internal energy of a solid increases, usually through the application of heat or pressure, such that the molecules become less ordered.


In ice cube melting into liquid water is a familiar example of the process. Another common example is melting butter in a hot pan.