Noun | 1. | LDL - a lipoprotein that transports cholesterol in the blood; composed of moderate amount of protein and a large amount of cholesterol; high levels are thought to be associated with increased risk of coronary heart disease and atherosclerosis lipoprotein - a conjugated protein having a lipid component; the principal means for transporting lipids in the blood LDL cholesterol - the cholesterol in low-density lipoproteins; the `bad' cholesterol; a high level in the blood is thought to be related to various pathogenic conditions |