freezing
All of the changes of state that occur between solid, liquid and gas are summarized in the diagram in the figure below. Freezing is the opposite of melting and both represent the equilibrium between the solid and liquid states. Evaporation occurs when a liquid turns to a gas. Condensation is the opposite of vaporization and both represent the equilibrium between the liquid and gas states. Deposition is the opposite of sublimation and both represent the equilibrium between the solid and gas states.