Definition of SET THEORY. : a branch of mathematics or of symbolic logic that deals with the nature and relations of sets. â set theoretic adjective. See set theory defined for kids. ADVERTISEMENT.
Broadly, the term lipid is encompasses fats (including saturated, monoglyceride, diglyceride and triglyceride), waxes, sterols, phospholipids in the membranes of cells and fat soluble vitamins. Lipid is a basic term representing a molecule that is fat soluble (vs. water soluble).
Lipids are a diverse group of fat-soluble biological molecules. Here is a look at different types of lipids and where they are found.1  Triacylglycerols or Triglycerides. 2  The largest class of lipids goes by different names: triacylglycerols, triglycerides, glycerolipids, or fats.ipids are a diverse group of fat-soluble biological molecules. Here is a look at different types of lipids and where they are found.