Definitions of S
  1. noun
    the 19th letter of the Roman alphabet
    synonyms: s
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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 cardinal compass point that is at 180 degrees
    synonyms: due south, south, southward
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    type of:
    cardinal compass point
    one of the four main compass points
  3. noun
    an abundant tasteless odorless multivalent nonmetallic element; best known in yellow crystals; occurs in many sulphide and sulphate minerals and even in native form (especially in volcanic regions)
    synonyms: atomic number 16, sulfur, sulphur
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    brimstone, native sulfur, native sulphur
    an old name for sulfur
    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
  4. noun
    (thermodynamics) a thermodynamic quantity representing the amount of energy in a system that is no longer available for doing mechanical work
    synonyms: entropy, randomness
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    conformational entropy
    entropy calculated from the probability that a state could be reached by chance alone
    type of:
    physical property
    any property used to characterize matter and energy and their interactions
  5. noun
    a unit of conductance equal to the reciprocal of an ohm
    synonyms: mho, reciprocal ohm, siemens
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    type of:
    conductance unit
    a measure of a material's ability to conduct an electrical charge
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