absorbent

1. (physiology, pluralized, now rare) The vessels by which the processes of absorption are carried on, as the lymphatics in animals, the extremities of the roots in plants.archaic

2. (medicine) 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. (physical chemistry) A liquid used in the process of separating gases or volatile liquids, in oil refining.physical