In lipids unsaturated refers to

the lack of double bonds between adjacent carbon atoms in a fatty acid.

In lipids, unsaturated refers to unsaturated fats.

Explanation:

Lipids are series of naturally happening natural compounds that you may know by their regular names: oils and fats. A key trait for this gathering of compounds is that they are not solvent in water.

There is a wide range of sorts of lipids. Instances of common lipids incorporate vegetable oil, butter, cholesterol, phospholipids, waxes, and fat-solvent vitamins. The basic traits for these compounds are that they are basically insoluble in water, yet dissolvable in at least one organic solvent.