Glycerides are esters of glycerol (propane-1,2,3-triol) with fatty acids, widely distributed in nature. They are by long-established custom subdivided into triglycerides, 1,2- or 1,3-diglycerides, and 1- or 2-monoglycerides, according to the number and position of acyl groups (not, as one might suppose, the number of glycerol residues). The recommended method for naming individual glycerides is mono-, di- or tri-O-acylglycerol, as appropriate. (Source: IUPAC Gold Book)
Glycerides or acylglycerols are the main constituent of vegetable oils and animal fats where fats have many important biological roles for living creatures. Since glycerides are esters of glycerol with fatty acids and glycerol has three hydroxy groups to be esterified with fatty acids, there can exist triglycerides, where all the hydroxyl groups are esterified, and also partial glycerides, where not all the hydroxyl groups (one or two but not all the three hydroxyl groups) are esterified. In addition to their biological roles, glycerides have industrial and commercial applications. For example, glycerides are used as precursors for fatty acids which have many applications like production of soaps and lubricants. As another example, some partial glycerides obtained from short chain fatty acids have excellent properties as pharmaceutical solvents.