This would be the Melting point because it is showing that at a certain heat it melts so therefore it is the point it melts and therefore called the melting point
At atmospheric pressure the amount of heat energy released or absorbed by a solid when it changes from solid state to liquid state at its melting point is known as latent heat of fusion.
For example, latent heat of fusion of water is 79.72 cal/g, that is, when water changes from ice to liquid state then heat released is 79.72 cal/g.
Hence, we can conclude that the correct term used to describe the amount of heat required to prompt a phase change is latent heat of fusion.