omega-3

adjective

ome·​ga-3 ō-ˈmā-gə-ˈthrē How to pronounce omega-3 (audio)
-ˈmē-, 
-ˈme- How to pronounce omega-3 (audio)
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Salmon Salmon is a great source of protein and is also rich in omega-3 fatty acids. — Jessica Swirble, Verywell Health, 3 July 2026 When part of a person’s regular diet, omega-3 fatty acids certainly play a vital role in maintaining health over the long term. — Drew Pittock, USA Today, 29 June 2026 Tuna Salad With Whole Grain Crackers Tuna packs plenty of protein and also provides heart-healthy omega-3 fats. — Lindsey Desoto, Health, 30 June 2026 The plan recommends supplements including multivitamins, omega-3 fatty acids, vitamin C, and CoQ10, taken in the morning and at night. — Emily Kay Votruba, EverydayHealth.com, 29 June 2026 See All Example Sentences for omega-3

Word History

First Known Use

1967, in the meaning defined above

Time Traveler
The first known use of omega-3 was in 1967

Browse Nearby Words

omega
omega-3
omega-6
See all Nearby Words

Cite this Entry

“Omega-3.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/omega-3. Accessed 7 Jul. 2026.

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Medical Definition

omega-3

adjective
ome·​ga-3 -ˈthrē How to pronounce omega-3 (audio)
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
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