Thermal energy transfer required to change a solid into liquid without changing its temperature is called?

Thermal energy transfer required to change a solid into liquid without changing its temperature is called?

ٹھوس کو اس کا درجہ حرارت تبدیل کیے بغیر مائع میں تبدیل کرنے کے لیے حرارتی توانائی کی منتقلی کو ____ کہتے ہیں؟
Explanation

Latent heat of fusion is the energy required to change a solid into a liquid (or vice versa) without changing its temperature. 

Latent heat of vaporization is the energy required to change a liquid into a gas (or vice versa) without changing its temperature.