Any of a group of phospholipids having the general composition CH₂OR₁⋅CHOR₂⋅CH₂OPO₂OHR₃, in which R₁ and R₂ are fatty acids and R₃ is choline, and with emulsifying, wetting, and antioxidant properties.

1. A mixture of phosphatides and oil obtained by drying the separate gums from the degumming of soybean oil; consists of the phosphatides (lecithin), cephalin, other fatlike phosphorus-containing compounds, and 30-35% entrained soybean oil; may be treated to produce more refined grades; used in foods, cosmetics, and paints. Also known as commercial lecithin; crude lecithin; soybean lecithin; soy lecithin.

2. A waxy mixture of phosphatides obtained by refining commercial lecithin to remove the soybean oil and other materials; used in pharmaceuticals. Also known as refined lecithin.