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

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

"Carrageenan, riboflavin, monosodium glutamate and 20 others that I can’t pronounce," he said, as one of the "MAHA moms" gravely intoned, "that stuff's really bad."

From Salon • Mar. 26, 2025

These included vitamins B12, B6 and D, folic acid and riboflavin which are essential for the development of foetuses in the womb.

From Science Daily • Dec. 5, 2023

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

Goodrich developed a process to use riboflavin, or vitamin B2, and rays of ultraviolet light to do the same thing.

From Washington Post • Jun. 30, 2021