Melting...
The name of the process is 'Melting'. It is that because the solid is melting into a liquid.
The process of a solid turning into a liquid is called "melting".
The process of a liquid changing into a solid is called solidification or freezing.
freezing
melting
The name for solid water is ice. It changes to a liquid when it melts.
Dissolving?
The scientific name for conversion of liquid to solid is called "Freezing" or "solidification".
Either freezing or crystallization.
Sublimation is the process in which solid directly changes into gaseous state. In the case of changing gas into solid, the process is known as deposition.
This change of phase is called freezing.
That process is referred to as "melting".