riboflavin

American  

[rahy-boh-fley-vin, rahy-boh-fley-, -buh-] / ˌraɪ boʊˈfleɪ vɪn, ˈraɪ boʊˌfleɪ-, -bə- /

Also riboflavine

noun

Biochemistry.

1. a vitamin B complex factor appearing as an orange-yellow, crystalline compound, C 1 7 H 2 0 N 4 O 6 , derived from ribose, essential for growth, found in milk, fresh meat, eggs, leafy vegetables, etc., or made synthetically, and used in enriching flour, in vitamin preparations, and in treating facial lesions.

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riboflavin British  

/ ˌraɪbəʊˈfleɪvɪn /

noun

1. Also: vitamin B2.   lactoflavin.  a yellow water-soluble vitamin of the B complex that occurs in green vegetables, germinating seeds, and in milk, fish, egg yolk, liver, and kidney. It is essential for the carbohydrate metabolism of cells. It is used as a permitted food colour, yellow or orange-yellow ( E101 ). Formula: C 17 H 20 N 4 O 6

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riboflavin Scientific  

/ rī′bō-flā′vĭn /

1. A water-soluble compound belonging to the vitamin B complex that is important in carbohydrate metabolism and the maintenance of mucous membranes. Riboflavin is found in milk, leafy vegetables, meat, and egg yolks. Also called vitamin B ₂ . Chemical formula: C ₁₇ H ₂₀ N ₄ O ₆ .

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Etymology

Origin of riboflavin

First recorded in 1930–35; ribo(se) + flavin

Example Sentences

Also known as riboflavin, vitamin B2 cannot be produced by the body and must come from food sources such as dairy products, eggs, meat, and green vegetables.

From Science Daily • May 15, 2026

She recommends focusing on other important B vitamins like B12 and riboflavin, also known as B2, which are typically found in dairy and animal foods.

From BBC • Apr. 22, 2026

Borage is a great addition to any diet — it's a good source of thiamin, folate and Vitamin B6, and a very good source of Vitamin A, Vitamin C, riboflavin and trace minerals.

From Salon • Jan. 31, 2024

FMN, which is derived from vitamin B2, also called riboflavin, is one of several prosthetic groups or co-factors in the electron transport chain.

From Textbooks • Jun. 9, 2022

Maple’s advocates also tout it as a source of minerals such as manganese and riboflavin.

From Washington Post • Apr. 6, 2018