tallow, solid fat extracted from the tissues and fatty deposits of animals, especially from suet (the fat of cattle and sheep). Pure tallow is white, odorless and tasteless; it consists chiefly of triglycerides of stearic, palmitic, and oleic acids. It is usually obtained commercially by heating suet under pressure in closed vessels. Tallow is used to make soap and candles. It was formerly in common use as a lubricant.