vitamin B₁₂

noun

-ˈbē-ˈtwelv 

1

: a complex cobalt-containing compound C₆₃H₈₈CoN₁₄O₁₄P that occurs especially in liver, is essential to normal blood formation, neural function, and growth, and is used especially in treating pernicious and related anemias and in animal feed as a growth factor

called also cyanocobalamin

2

: any of several compounds similar to vitamin B₁₂ in action but having different chemistry

Examples of vitamin B₁₂ in a Sentence

Recent Examples on the Web

Oral vitamin B12 supplements are usually sufficient to maintain daily requirements. —Emmanuella Ogbonna, Health, 29 Apr. 2025

One of the other major risks of nitrous oxide abuse is the disruption of vitamin B12 metabolism, Hadland says. —Ella Jeffries, Smithsonian Magazine, 8 Apr. 2025

Because vitamin B12 is primarily found in meat, fish, dairy and eggs, vegetarians and vegans should consider taking a vitamin B12 supplement. —Lina Begdache, The Conversation, 7 Jan. 2025

Specific vitamins like biotin, iron, zinc, vitamin C, vitamin D, and vitamin B12 are essential for nail growth, adds Dr. Patel, and deficiencies can not only lead to slow-growing nails, but also brittle or ridged ones. —Catharine Malzahn, Glamour, 3 Apr. 2025

These include protein, vitamin B12, vitamin D, and minerals such as calcium, iron, and zinc, high in meat or animal by-products. —Angelica Bottaro, Verywell Health, 1 Apr. 2025

Without proper supplementation, both groups face a higher risk of vitamin B12 deficiency, lower vitamin D levels, reduced iron stores, and iodine deficiency, which could impact thyroid function. —Josh Hammer, Newsweek, 19 Mar. 2025

Red meat can be a valuable source of important nutrients, including zinc, iron, protein, and vitamin B12. —Roxana Ehsani, Verywell Health, 21 Mar. 2025

Sardines These small fish, especially when eaten whole, are a powerhouse of nutrients: Sardines contain vitamin D, selenium, and vitamin B12. —Alessandra Signorelli, Vogue, 11 Mar. 2025

Word History

First Known Use

1948, in the meaning defined at sense 1

Kids Definition

vitamin B₁₂

noun

-ˈbē-ˈtwelv

: a member of the vitamin B complex that contains cobalt, occurs especially in liver, and is needed for normal blood formation, nerve function, and growth

also : any of several other compounds with similar activity

Medical Definition

vitamin B₁₂

noun

-ˈbē-ˈtwelv 

1

: a complex cobalt-containing compound C₆₃H₈₈CoN₁₄O₁₄P found in animal products (as meat and eggs) that is essential to normal blood formation, neural function, and growth and is used especially in treating pernicious and related anemias and in animal feed as a growth factor

called also cyanocobalamin

2

: any of several compounds similar to vitamin B₁₂ in action but having different chemistry