When there is liquid in the process of vaporizing or boiling into a vapor, this process is called:

The process of a liquid vaporizing or boiling into a vapor is referred to as "saturated liquid." In this context, a saturated liquid is the state of a substance at a specific pressure and temperature where it coexists with its vapor phase. During this phase change, energy is added to the liquid, leading to vaporization without a temperature change until all the liquid has turned into vapor.

In refrigeration and air conditioning, understanding the concepts of saturated liquid and vapor is crucial when discussing the operation of HVAC systems. The notion of saturation indicates that the liquid is at the boiling point for its specific pressure and that any additional heat will lead to the transition from liquid to vapor.

The other terms relate to different processes: "saturated vapor" refers to the state where a vapor is in equilibrium with its liquid at the saturation temperature, "latent heat of fusion" pertains to the energy required to change a solid into a liquid at its melting point, and "latent heat of condensation" is the heat released when a vapor turns into a liquid. These concepts, while related to phase changes, specifically describe different scenarios and are not applicable to the process of vaporization described in the question.