noun
thermal diffusion
Technical term in physics and engineering for the movement of heat through a medium due to a temperature gradient.
熱拡散は、温度差によって熱が移動する現象です。
Thermal diffusion is a phenomenon in which heat moves due to a temperature difference.
熱伝導 (thermal conduction) refers specifically to heat transfer through direct contact within a material, while 熱拡散 is a broader term for heat spreading, often involving convection or radiation as well.
Compound of 熱 (heat) and 拡散 (diffusion). The term is a direct calque from English 'thermal diffusion'.