Coated stent: A tiny cage to prop open an artery and prevent it from closing again, that is coated with a drug. The stent is inserted into a coronary artery, usually just after an angioplasty has been done, to keep open the vessel. The stent slowly releases the drug with which it is coated. Coated stents reduce the risk of artery re-narrowing (restenosis) after angioplasty. Also known as a medicated stent, drug-coated stent, drug-eluting stent, eluting stent.