choline

n. chemical substance present in vitamin B

Choline is an organic compound, classified as an essential nutrient and usually grouped within the Vitamin B complex. This natural amine is found in the lipids that make up cell membranes and in the neurotransmitter acetylcholine. Adequate intakes (AI) for this micronutrient of between 425 to 550 milligrams daily, for adults, have been established by the Food and Nutrition Board of the Institute of Medicine of the National Academy of Sciences.
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Choline /cho·line/ a quaternary amine, often classified as a member of the B vitamin complex; it occurs in phosphatidylcholine and acetylcholine, is [more]Choline - Community and Resources

Noun
1. a B-complex vitamin that is a constituent of lecithin; essential in the metabolism of fat
(hypernym) B-complex vitamin, B complex, vitamin B complex, vitamin B, B vitamin, B

(n.)
See Neurine.