/ Dictionary / Index L low-density lipoprotein: Meaning and Definition of Find definitions for: low'-den'sity lipopro'tein Pronunciation: [key] — Biochem. Biochem. a plasma protein that is the major carrier of cholesterol in the blood: high levels are associated with atherosclerosis. Abbr.: LDL Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease. low-density low-density polyethylene Related Content Daily Word Quiz: lunar Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language