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b

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
    (physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter
    synonyms: barn
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    type of:
    area unit, square measure
    a system of units used to measure areas
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