What is the term used to describe a change in the state of matter from solid to liquid?

The term used to describe the change in the state of matter from solid to liquid is known as melting. This process occurs when a solid absorbs heat, causing its particles to gain energy and move more freely. As a result, the rigid structure of the solid breaks down, allowing the material to transition into a liquid form. This transformation is commonly observed in substances like ice becoming water as it warms up. Understanding this phase change is fundamental in the study of thermodynamics and the behavior of materials under varying temperatures.