1. [n]  a material having capacity or tendency to absorb another substance
2. [adj]  having power or capacity or tendency to absorb or soak up (liquids); "as absorbent as a sponge"

ABSORBENT is a 9 letter word that starts with A.

1. \Ab*sorb"ent\, a. [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.
   

2. \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.