riboflavin

noun

ri·​bo·​fla·​vin ˌrī-bə-ˈflā-vən 

ˈrī-bə-ˌflā-

: a yellow crystalline compound C₁₇H₂₀N₄O₆ of the vitamin B complex that occurs both free (as in milk) and combined (as in liver) as a component of coenzymes (such as FMN) which are essential to normal metabolism

called also vitamin B₂

Examples of riboflavin in a Sentence

Recent Examples on the Web

This color comes from high concentrations of riboflavin, or vitamin B2, which is safe to consume. —Anne Wolf, Martha Stewart, 9 May 2026

However, little research has explored the long-term effects of taking the vitamins on stroke risk, the optimal intake for preventing stroke, and whether other B vitamins—particularly thiamin, riboflavin, and niacin—might also have an effect. —Zoe Cunniffe, Health, 30 Apr. 2026

Along with nonfat milk, sugar, and palm oil, Nela includes vitamin A palmitate and riboflavin to fortify the finished product. —Sam Stone, Bon Appetit Magazine, 16 Apr. 2026

These include vitamins like riboflavin (B2), biotin (B7) and folate (B9). —Helen Carefoot, Flow Space, 2 Feb. 2026

Word History

Etymology

International Scientific Vocabulary ribo- + Latin flavus yellow — more at blue

First Known Use

1935, in the meaning defined above

Rhymes for riboflavin

• craven
• flavin
• graven
• haven
• maven
• pavan
• raven
• shaven
• engraven
• unshaven

Kids Definition

riboflavin

noun

ri·​bo·​fla·​vin ˌrī-bə-ˈflā-vən 

: a vitamin of the vitamin B complex that helps growth and is found both free (as in milk) and combined with other substances (as in liver)

called also vitamin B₂

Medical Definition

riboflavin

noun

ri·​bo·​fla·​vin ˌrī-bə-ˈflā-vən, ˈrī-bə-ˌ 

variants also riboflavine

-ˌvēn 

: a yellow crystalline compound C₁₇H₂₀N₄O₆ that is a growth-promoting member of the vitamin B complex and occurs both free (as in milk) and combined (as in liver)

called also lactoflavin, ovoflavin, vitamin B₂