vitamin B12

American  

noun

1. a deep-red crystalline, water-soluble solid, C 63 H 88 N 14 O 14 PCo, obtained from liver, milk, eggs, fish, oysters, and clams: a deficiency causes pernicious anemia and disorders of the nervous system.

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vitamin B12 British  

noun

1. another name for cyanocobalamin

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vitamin B12 Scientific  

1. A water-soluble, complex organic compound containing cobalt, found especially in meat, liver, eggs, milk, and milk products. Vitamin B ₁₂ is necessary for the synthesis of DNA by the body, for the production of blood cells, and for maintaining the health of nerves. A deficiency of vitamin B ₁₂ in the diet results in pernicious anemia.

2. Also called cobalamin cyanocobalamin

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Etymology

Origin of vitamin B12

First recorded in 1945–50

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How does vitamin-b12 compare to similar and commonly confused words? Explore the most common comparisons:

• vitamin B12 vs. B complex

Example Sentences

See Examples For:

vitamin B12

Jack mackerel contains about half as much omega-3 and around a third as much vitamin B12 as traditional mackerel.

From BBC ● Sep. 12, 2026

That limitation has prevented conventional Spirulina from serving as a reliable replacement for animal-sourced vitamin B12.

From Science Daily ● Aug. 30, 2026

By changing the light environment in which Spirulina grows, the researchers were able to encourage production of biologically active vitamin B12.

From Science Daily ● Aug. 30, 2026

Dr. Asaf Tzachor explains, "the findings demonstrate that photosynthetically controlled Spirulina can produce desirable levels of active vitamin B12, offering a sustainable alternative to traditional animal-source foods."

From Science Daily ● Aug. 30, 2026

We are, after all, a planet where the rain contains vitamin B12!

From "The Lives of a Cell" by Lewis Thomas