noun Download 🔗Share Any lipid, such as lecithin or cephalin, consisting of a diglyceride combined with a phosphate group and a simple organic molecule such as choline or ethanolamine; they are important constituents of biological membranes. Examples : "The phospholipid is a key building block of the cell membrane, forming a barrier that protects the inside of the cell. " biochemistry biology compound substance chemistry physiology medicine organism structure Chat with AIVocabulary GamePractice Reading