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

See Examples For:

riboflavin

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

Results showed that nine out of ten women had marginal or low levels of folate, riboflavin, vitamins B12 and D around the time of conception, and that many developed vitamin B6 deficiency in late pregnancy.

From Science Daily ● Dec. 5, 2023

Similarly, multivitamins typically contain riboflavin, or vitamin B2, which causes your urine to turn bright yellow when it is cleared.

From Salon ● Jun. 19, 2022

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

A chapter marked with sticky notes was “astounding,” Goodrich said, because it described the unique optical properties of riboflavin.

From Washington Post ● Jun. 30, 2021