Melting n. Liquefaction; the act of causing (something) to melt, or the process of becoming melted. Melting point (Chem.), the degree of temperature at which a solid substance melts or fuses; as, the melting point of ice is 0° Centigrade or 32° Fahr., that of urea is 132° Centigrade. Pressure affects the melting point somewhat, and if not specified the melting point is usually taken to be at atmospheric pressure.