omega-3

adjective

ome·​ga-3 ō-ˈmā-gə-ˈthrē 

-ˈmē-,

-ˈme- 

: being or composed of polyunsaturated fatty acids that have the final double bond in the hydrocarbon chain between the third and fourth carbon atoms from the end of the molecule opposite that of the carboxyl group and that are found especially in fish, fish oils, green leafy vegetables, and some nuts and vegetable oils compare omega-6

omega-3 noun

Examples of omega-3 in a Sentence

Recent Examples on the Web

In addition to fiber and magnesium, these small seeds are one of the best sources of omega-3 fatty acids after fish and other seafood. —Cristina Mutchler, Verywell Health, 27 June 2025

Same for quitting smoking, getting a good night’s sleep, limiting alcohol, and adding foods rich in omega-3s. —Time, 26 June 2025

Seafood is a main source of omega-3s, and eating more fatty fish, like sardines, could reduce your need for omega-3 supplements.910 Fatty fish are also high in nutrients like: Vitamin D, in particular, plays important roles in immune, brain, and skeletal health, and is only found in a few foods. —Jillian Kubala, Health, 25 June 2025

Incorporating fish oil in your diet comes with many benefits for your overall health, thanks to the omega-3 fatty acids. —Christina Pérez, Vogue, 23 June 2025

Word History

First Known Use

1967, in the meaning defined above

Medical Definition

omega-3

adjective

ome·​ga-3 -ˈthrē 

variants also Omega-3

: being or composed of polyunsaturated fats that have the first double bond in the hydrocarbon chain occurring between the third and fourth carbon atoms from the end of the molecule most distant from the carboxylic acid group and that are found especially in fish, fish oils, green leafy vegetables, and some nuts and seeds

The two main omega-3 fatty acids in fish oil … appear to reduce the risk of dying from sudden cardiac arrest by about 30 percent.

—Nutrition Action Health Letter

compare omega-6

omega-3 noun

also Omega-3

Some plants, such as linseed, naturally produce an omega-3 called alpha-linolenic acid (ALA), and one way to increase the amount of omega-3 in our diet is to eat these plants …

—Andy Coghlan, New Scientist