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

Salmon is an excellent source of anti-inflammatory omega-3 fats, protein, and several essential vitamins and minerals. —Jillian Kubala, Health, 7 Aug. 2025

The combination of beetroot juice and chia seeds provides a rich source of fiber, protein, omega-3 fatty acids, antioxidants, and various vitamins and minerals. —Lana Barhum, Verywell Health, 6 Aug. 2025

Supplements were provided to everyone in the intervention group, including a daily multivitamin, omega-3 fatty acids with curcumin, coenzyme Q10, vitamin C and B12, magnesium, a probiotic, and Lion’s mane mushroom. —Sandee Lamotte, CNN Money, 29 July 2025

Salmon and Other Fatty Fish Another food rich in omega-3 fatty acids is fatty fish, which include salmon, mackerel, herring, sardines, and tuna. —Audrey Noble, Vogue, 21 July 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