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h

Definitions of h
  1. noun
    the 8th letter of the Roman alphabet
    synonyms: H
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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 constant of proportionality relating the energy of a photon to its frequency; approximately 6.626 x 10^-34 joule-second
    synonyms: Planck's constant
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    type of:
    constant of proportionality, factor of proportionality
    the constant value of the ratio of two proportional quantities x and y; usually written y = kx, where k is the factor of proportionality
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