# lipid

/ˈɫaɪpəd/ (US) · /lˈɪpɪd/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/lipid
Updated: 2026-05-07

## Definition

a type of natural oil, fat, or wax that does not dissolve in water. These are important parts of living cells and help your body store energy.

For teachers: any of a class of organic compounds that are fatty acids or their derivatives and are insoluble in water but soluble in organic solvents. Includes many natural oils, waxes, and steroids.

## Examples

- The doctor checked the lipid levels in my blood.
- A healthy diet requires a balance of different nutrients, including proteins, carbohydrates, and lipids.
- The cell membrane is primarily composed of a lipid bilayer, which acts as a selective barrier to control the movement of substances in and out of the cell.

## Usage notes

- Often used in the plural when referring to medical test results or biological categories.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.