This article waslast modified on July 10, 2017.
Any of a group of fats and fat-like substances, including oils, waxes, steroids, and triglycerides. Lipids are easily stored in the body, and triglycerides serve as a fuel source. Some (such as cholesterol and phospholipids) are an important constituent of cell structures and are involved in many biological functions. Lipids can combine with other compounds to form complexes, such as lipoproteins, phospholipids, and glycolipids.