Chemically speaking, this molecule is "halfway" in between Sorbitan Oleate and Sorbitan Trioleate, that means that it's also an attachment of sorbitan (a dehydrated sorbitol (sugar) molecule) with the unsaturated fatty acid Oleic Acid, but inside of a ratio of two:3 hence the "Sesqui" component during the molecule's title. Not merely a simple mois