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lipid

American  
[lip-id, lahy-pid] / ˈlɪp ɪd, ˈlaɪ pɪd /
Also lipide

noun

Biochemistry.
  1. any of a group of organic compounds that are greasy to the touch, insoluble in water, and soluble in alcohol and ether: lipids comprise the fats and other esters with analogous properties and constitute, with proteins and carbohydrates, the chief structural components of living cells.


lipid British  
/ ˈlɪpɪd, ˈlaɪpɪd /

noun

  1. Former name: lipoidbiochem any of a large group of organic compounds that are esters of fatty acids ( simple lipids , such as fats and waxes) or closely related substances ( compound lipids , such as phospholipids): usually insoluble in water but soluble in alcohol and other organic solvents. They are important structural materials in living organisms

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

lipid Scientific  
/ lĭpĭd /
  1. Any of a large group of organic compounds that are oily to the touch and insoluble in water. Lipids include fatty acids, oils, waxes, sterols, and triglycerides. They are a source of stored energy and are a component of cell membranes.


Etymology

Origin of lipid

First recorded in 1920–25; lip- + -id 3

Explanation

A lipid is a waxy or oily organic molecule that is insoluble in water. Certain vitamins, like A, D, E, and K, are lipids. Lipids are sometimes described as fat-soluble, rather than water-soluble. A more precise way to think of them is "soluble in organic solvents." The same way a dollop of oil floats on a bowl of water, or a greasy pan only gets clean once you've added dish soap to the water, a lipid keeps itself separate from water. This gives it the ability to store energy and provide insulation. Lipid is derived from the Greek lipos, "fat or grease."

Keep Reading on Vocabulary.com

Vocabulary lists containing lipid

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"The pattern included reduced expression of genes tied to extracellular matrix organization and endothelial integrity, alongside broader changes consistent with altered lipid handling after injury."

From Science Daily • Apr. 26, 2026

Scientists have tested hundreds of new lipid combinations and used artificial intelligence to explore countless formulations.

From Science Daily • Apr. 20, 2026

In the liver, fat accumulation increased, along with the activity of genes linked to fatty acid production and lipid transport.

From Science Daily • Apr. 14, 2026

The bots scanned my lipid panels and Apple Watch heart-rate data.

From The Wall Street Journal • Apr. 4, 2026

Before Citra left home, Mrs. Yeltner had reset her lipid point to svelte.

From "Scythe" by Neal Shusterman