Chemically speaking, this molecule is "midway" in between Sorbitan Oleate and Sorbitan Trioleate, which means that it's also an attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the unsaturated fatty acid Oleic Acid, but in the ratio of two:three hence the "Sesqui" section in the molecule's title. We do a Best of INCIDecoder ema