Meaning of DIFFUSION in English
( n. )
The act of passing by osmosis through animal membranes, as in the distribution of poisons, gases, etc., through the body. Unlike absorption, diffusion may go on after death, that is, after the blood ceases to circulate.
Webster's Revised Unabridged English Dictionary. Пересмотренный полный словарь английского языка Webster. 2012