Definitions of B
  1. noun
    the 2nd letter of the Roman alphabet
    synonyms: b
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    type of:
    alphabetic character, letter, letter of the alphabet
    the conventional characters of the alphabet used to represent speech
  2. noun
    the blood group whose red cells carry the B antigen
    synonyms: group B, type B
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    type of:
    blood group, blood type
    human blood cells (usually just the red blood cells) that have the same antigens
  3. noun
    originally thought to be a single vitamin but now separated into several B vitamins
    synonyms: B complex, B vitamin, B-complex vitamin, vitamin B, vitamin B complex
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    a B-complex vitamin that is a constituent of lecithin; essential in the metabolism of fat
    an optically inactive alcohol that is a component of the vitamin B complex
    pantothen, pantothenic acid
    a vitamin of the vitamin B complex that performs an important role in the oxidation of fats and carbohydrates and certain amino acids; occurs in many foods
    aneurin, antiberiberi factor, thiamin, thiamine, vitamin B1
    a B vitamin that prevents beriberi; maintains appetite and growth
    antipernicious anemia factor, cobalamin, cyanocobalamin, vitamin B12
    a B vitamin that is used to treat pernicious anemia
    hepatoflavin, lactoflavin, ovoflavin, riboflavin, vitamin B2, vitamin G
    a B vitamin that prevents skin lesions and weight loss
    adermin, pyridoxal, pyridoxamine, pyridoxine, vitamin B6
    a B vitamin that is essential for metabolism of amino acids and starch
    folacin, folate, folic acid, pteroylglutamic acid, pteroylmonoglutamic acid, vitamin Bc, vitamin M
    a B vitamin that is essential for cell growth and reproduction
    niacin, nicotinic acid
    a B vitamin essential for the normal function of the nervous system and the gastrointestinal tract
    biotin, vitamin H
    a B vitamin that aids in body growth
    type of:
    water-soluble vitamin
    any vitamin that is soluble in water
  4. noun
    a logarithmic unit of sound intensity equal to 10 decibels
    synonyms: Bel
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    type of:
    sound unit
    any acoustic unit of measurement
  5. noun
    a trivalent metalloid element; occurs both in a hard black crystal and in the form of a yellow or brown powder
    synonyms: atomic number 5, boron
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    type of:
    chemical element, element
    any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
  6. noun
    aerobic rod-shaped spore-producing bacterium; often occurring in chainlike formations; found primarily in soil
    synonyms: bacillus
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    Bacillus anthracis, anthrax bacillus
    a species of bacillus that causes anthrax in humans and in animals (cattle and swine and sheep and rabbits and mice and guinea pigs); can be used a bioweapon
    Bacillus globigii, Bacillus subtilis, grass bacillus, hay bacillus
    a species of bacillus found in soil and decomposing organic matter; some strains produce antibiotics
    Yersinia pestis
    a bacillus bacterium that causes the plague; aerosolized bacteria can be used as a bioweapon
    type of:
    eubacteria, eubacterium, true bacteria
    a large group of bacteria having rigid cell walls; motile types have flagella
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