cod-liver oil
noun
cod-liv·er oil
: an oil obtained from the liver of the cod and closely related fishes and used as a source of vitamins A and D
Example Sentences
Recent Examples on the Web And don’t turn your nose up at a spoonful of good old-fashioned cod-liver oil, either. 
Kathleen Squires, WSJ, 28 Jan. 2022 Similar products followed, but most people used homemade recipes with affordable ingredients such as canned milk and Karo syrup, and supplemented babies’ diets with orange juice and cod-liver oil to prevent scurvy and rickets. Alice Callahan, Smithsonian, 25 Oct. 2019 The scientists gave patients scheduled for knee-replacement surgery either 1,000 milligrams of cod-liver oil or placebo. Houston Chronicle, 1 July 2018 Many doctors perceive the use of cod-liver oil for joint pain as an old wives' tale. Houston Chronicle, 1 July 2018
Kathleen Squires, WSJ, 28 Jan. 2022 Similar products followed, but most people used homemade recipes with affordable ingredients such as canned milk and Karo syrup, and supplemented babies’ diets with orange juice and cod-liver oil to prevent scurvy and rickets. Alice Callahan, Smithsonian, 25 Oct. 2019 The scientists gave patients scheduled for knee-replacement surgery either 1,000 milligrams of cod-liver oil or placebo. Houston Chronicle, 1 July 2018 Many doctors perceive the use of cod-liver oil for joint pain as an old wives' tale. Houston Chronicle, 1 July 2018 Word History
First Known Use
1754, in the meaning defined above
Medical Definition
cod-liver oil
noun
: a pale yellow fatty oil obtained from the liver of the cod (Gadus morhua) and related fishes and used in medicine (as in the prophylaxis of rickets) chiefly as a source of vitamins A and D compare fish-liver oil