adsorbent

Adsorption is a process that occurs when a gas or liquid solute accumulates on the surface of a solid or, more rarely, a liquid (adsorbent), forming a molecular or atomic film (the adsorbate). It is different from absorption, in which a substance diffuses into a liquid or solid to form a solution. The term sorption encompasses both processes, while desorption is the reverse process.
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Noun
1. a material having capacity or tendency to adsorb another substance
(synonym) adsorbent material
(hypernym) sorbent, sorbent material
(derivation) adsorb
Adjective
1. having capacity or tendency to adsorb or cause to accumulate on a surface
(synonym) adsorptive, surface-assimilative
(antonym) nonadsorbent, nonadsorptive
(similar) chemisorptive, chemosorptive

v. adsorb, attract gas or liquid to the surface of a solid (Chemistry)

adjective
capable of adsorption

 Say it 
Compare with absorbent .A substance that collects molecules of another substance on its surface. For example, gases that make water taste bad are strongly adsorbed on activated charcoal granules in water filters.