Source : Webster's Revised Unabridged Dictionary (1913)

Sorbent \Sorb"ent\, n. [L. sorbens, p. pr. of sorbere to suck
   in, to absorb.]
   An absorbent. [R.]

Source : WordNet®

sorbent
     n : a material that sorbs another substance; i.e. that has the
         capacity or tendency to take it up by either absorption
         or adsorption [syn: {sorbent material}]