absorption:

(chemistry) a process in which one substance permeates another; a 
fluid permeates or is dissolved by a liquid or solid 
(physics) the process in which incident radiated energy is 
retained without reflection or transmission on passing through a 
medium; "the absorption of photons by atoms or molecules" 
(nutrition) the process of absorbing nutrients into the body after 
digestion 

Absorption is the uptake of fluids or other substances by the 
tissues of the body. Digested food is absorbed into the blood and 
lymph from the alimentary canal. Most absorption of food occurs in 
the small intestine. 

The uptake of water or dissolved chemicals by a cell or an 
organism (as tree roots absorb dissolved nutrients in soil)

The process of taking in, as when a sponge takes up water. 
Chemicals can be absorbed into the bloodstream after breathing or 
swallowing. Chemicals can also be absorbed through the skin into 
the bloodstream and then transported to other organs. Not all of 
the chemical breathed, swallowed, or touched is always absorbed.