Definition of fish oil
: a fatty oil from the bodies of various fishes (as menhaden or sardines) that contains large amounts of unsaturated fatty acids and is used as a dietary supplement and in making various products (as cosmetics and paints)
First Known Use of fish oil
Medical Definition of fish oil
: a fatty oil that is obtained from oily fish (such as herring or menhaden), contains large amounts of unsaturated fatty acids, and is used as a dietary supplement and in making various products (such as protective coatings, cosmetics, and animal feed) <Scientists learned some time ago that there are significant health benefits from consuming omega-3 fatty acids, which are found mostly in fish oils, algal oils, and linseed oil.—Felicia M. Willis, Today's Chemist at Work, October 2004>
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