What does absorbent mean?
The definition of absorbent
Ab*sorb”ent, a.
Etym: [L. absorbens, p. pr. of absorbere.]

Absorbing; swallowing; absorptive. Absorbent ground (Paint.), a ground prepared for a picture, chiefly with distemper, or water colors, by which the oil is absorbed, and a brilliancy is imparted to the colors.

Ab*sorb”ent, n.
1 Anything which absorbs. The ocean, itself a bad absorbent of heat. Darwin.
2 (Med.)
Any substance which absorbs and neutralizes acid fluid in the stomach and bowels, as magnesia, chalk, etc.; also a substance e. g., iodine) which acts on the absorbent vessels so as to reduce enlarged and indurated parts.
3 pl. (Physiol.)
The vessels by which the processes of absorption are carried on, as the lymphatics in animals, the extremities of the roots in plants.