Permeable (9)
'permeable' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for absorbent that I've seen before include "drinking" , "receptive" , "Bob ran set (anag.)" , "Sucking up liquid" , "Such material is able to take in water" .)
'permeable' is the definition.
(similar in meaning)
This is the entire clue.
(Other definitions for porous that I've seen before include "Able to absorb fluids" , "Riddled with tiny holes like skin" , "Allowing air/liquid to pass through" , "With small holes for liquid to pass through" , "Pitted with little holes, like skin" .)