1. That which is capable of attracting and absorbing substances into itself: "Randy brought a new sponge which is the best absorbent he has ever used."
2. A product or substance which can absorb liquids or gases: "The new powder-like substance is a great absorbent when cleaning up the oils and grease at the mechanic's garage."
2. Any substance that takes in fluids through its sensible or insensible porosity; applied in a special sense in medicine to such substances as chalk or magnesia that take in the acidity of the stomach: "Certain forms of magnesium can work as an absorbent when administered as a laxative."