cholesterol

noun

cho·​les·​ter·​ol kə-ˈle-stə-ˌrȯl 

-ˌrōl

: a waxy, fat-like substance C₂₇H₄₆O that is found in the cells, tissues, and body fluids of humans and animals and that serves as a component of cell membranes and functions as a precursor of vitamin D and steroid hormones (such as cortisol and estrogen)

Note: Cholesterol is produced primarily in the liver and is also derived from dietary sources (such as meat, eggs, and dairy products). It is carried in the bloodstream in the form of lipoproteins, and as a constituent of LDL it may contribute to arterial plaque formation leading to atherosclerosis.

The liver uses cholesterol to produce bile acids, which emulsify fats in the small intestine so they can be more readily absorbed and digested.

—Deane Morrison

Doctors use statins to treat high cholesterol in patients whose condition has not responded to a treatment of dietary changes.

—Joseph Gerstein

In many cases, the flow of oxygen-bearing blood is hindered by a buildup of cholesterol in the coronary arteries …

—Michael Waldholz et al.

Despite being much maligned in the popular press, cholesterol plays a crucial role in organizing cell membranes and controlling their physical properties.

—Amanda Yarnell

see also bad cholesterol, good cholesterol

Examples of cholesterol in a Sentence

Did your doctor check your cholesterol?

Recent Examples on the Web

Some research suggests that flaxseed (a good source of omega-3s) and sunflower seed oils may lower LDL (bad) cholesterol, which can lead to heart disease and strokes, and raise HDL (good) cholesterol, which supports a healthy heart. —Lauren O'Connor, Health, 4 Aug. 2025

Healthwise, cooking oil made from sunflowers is the preferred vegetable oil due to its unsaturated fats and, especially, its oleic acids that help increase good (HDL) cholesterol. —Joshua Siskin, Oc Register, 2 Aug. 2025

Research shows that eating hazelnuts may lower blood pressure and cholesterol levels.19 Pecans are known for their tasty flavor in pies and cakes. —Jamie Johnson, Verywell Health, 28 July 2025

Higher fiber intake has been linked to making bowel movements more regular, stabilizing blood sugar levels, lowering total and LDL cholesterol, reducing blood pressure and balancing the pH in your intestines. —Bruce Y. Lee, Forbes.com, 24 July 2025

Word History

Etymology

International Scientific Vocabulary, from chol- + Greek stereos solid

First Known Use

1894, in the meaning defined above

Phrases Containing cholesterol

• bad cholesterol
• cholesterol level
• good cholesterol
• high cholesterol

Rhymes for cholesterol

• artisanal
• autosomal
• azimuthal
• ergosterol
• lysosomal
• microsomal
• mycorrhizal
• neanderthal
• resorcinol
• ribosomal
• salbutamol
• aerosol

Kids Definition

cholesterol

noun

cho·​les·​ter·​ol kə-ˈles-tə-ˌrōl 

-ˌrȯl

: a waxy substance that is present in animal cells and tissues, is important in bodily processes, and may be related to the abnormal thickening and hardening of arteries when too much is present

Medical Definition

cholesterol

noun

cho·​les·​ter·​ol kə-ˈles-tə-ˌrōl, -ˌrȯl 

: a waxy, fat-like steroid alcohol C₂₇H₄₆O that is found in the cells, tissues, and body fluids of humans and animals, serves as a component of cell membranes and functions as a precursor of vitamin D and steroid hormones, and as a constituent of LDL may contribute to arterial plaque formation leading to atherosclerosis

Note: Cholesterol is produced primarily in the liver and is also derived from dietary sources (such as meat, eggs, and dairy products). It is carried in the bloodstream in the form of lipoproteins.

Cholesterol is a lipid present in the cell membrane and subcellular organelles of tissues throughout the body. … In addition, cholesterol serves as the building block for all steroid hormones including cortisol, aldosterone, estrogen, and testosterone.

—Sarah de Ferranti and David S. Ludwig, The New England Journal of Medicine

… the drug reduces the production of cholesterol in the liver, decreasing the amount of artery-clogging cholesterol circulating in the bloodstream.

—Newsweek