an oily organic compound insoluble in water but soluble in organic solvents; essential structural component of living cells (along with proteins and carbohydrates)
"The cell membrane is primarily composed of a lipid bilayer that acts as a barrier to keep the cell's internal environment stable."
Any of a group of organic compounds including the fats, oils, waxes, sterols, and triglycerides. Lipids are characterized by being insoluble in water, and account for most of the fat present in the human body.
"The lipid profile test measures cholesterol levels to assess how much of these water-insoluble organic compounds make up the fat stored in your body."
In plain English: A lipid is any fat, oil, or waxy substance that doesn't mix with water and serves as an important energy source for your body.
"Your body breaks down fats, which are lipids, to use them for energy."
Usage: Lipid is often confused with "lip" due to their similar spelling but have entirely different meanings; use it only when referring to biological compounds like fats or oils. Avoid using the plural form "lipoide" as this is a misspelling of the correct term "lipids."
The word lipid was borrowed into English from the French term lipide, which was created in 1923 to describe animal fats. It combines an ancient Greek root meaning "fat" with a suffix used for chemical compounds, effectively naming this class of substances as they were first identified by scientists.