diffusion — An Etymological Dictionary of Astronomy and Astrophysics

diffusion

پخش

paxš (#)

Fr.: diffusion

Movement of a gas or liquid as a result of the random thermal motion of its atoms or molecules.
The random spreading out of a beam of radiation on reflection (→ diffuse reflection) or transmission through a translucent medium (such as amber, milk, or frosted glass).
In chemical thermodynamics, the process of attaining an equilibrium distribution of the → concentration within the phases. A result of diffusion at constant equilibrium is the equalization of the → chemical potentials.
Related terms:
→ diffraction; → dispersion; → distribution; → scatter; → scattering.

Etymology (EN): L. diffusionem, from stem of diffundere “scatter, pour out,” from dif- “apart, in every direction,” → dis-,

fundere “to melt, cast, pour out,” from PIE *gheud-, from root *gheu- “to pour.”

Etymology (PE): Paxš, verbal noun and stem of paxšidan→ diffuse.

An Etymological Dictionary of Astronomy and Astrophysics