Adsorb

 

Accumulation of a substance at an interface, i.e. is held at or on the surface.

Note the differences below:

 

https://www.nfsa.gov.au/sites/default/files/uploads/2010/08/23/adsorb.gif

https://www.nfsa.gov.au/sites/default/files/uploads/2010/08/23/absorb.gif