Fatty substances, including cholesterol and triglycerides, that are present in blood and body tissues. Source

One of the four classes of organic macromolecules. Lipids function in the long-term storage of biochemical energy, insulation, structure and control. Examples of lipids include the fats, waxes, oils and steroids (eg testosterone, cholesterol).Source

Fats, oils, and waxes that serve as building blocks for cells or as energy sources for the body.Source

The nutritionally important lipids are fats (solid) and oils (liquids) that consist of fatty acids with 12- 20 carbons. Most of the lipid found in food is in the form of triglycerides which are fatty acid esters of glycerol. Other types of dietary lipids are cholesterol and phospholipids. The dietary requirement for lipids can be satisfied entirely by consumption of sufficient amounts of linoleic and linolenic acids. Source

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Lipids: Fats, Oils, Waxes, etc: All Lipids are hydrophobic: that’s the one property they have in common. This group of molecules includes fats and oils, waxes, phospholipids, steroids (like cholesterol), and some other related compounds.

Lipids: The lipids are a large and diverse group of naturally occuring organic compounds that are related by their solubility in nonpolar organic solvents (e.g. ether, chloroform, acetone & benzene) and general insolubility in water.

The Functions of Lipids: here are several different forms of lipids in the body, and each serve a specific and very important purpose. The first group of lipids is a group devoted to the storage of energy.

The Lipid Building Blocks: The common building block for most of the different types of lipids is the fatty acid. Fatty acids are composed of a chain of methylene groups with a Carboxyl functional group at one end.