sexagenary arithmetic

Sexagenary \Sex*ag"e*na*ry\, a. [L. sexagenarius, fr. sexageni
   sixty each, akin to sexaginta sixty, sex six: cf.
   sexag['e]naire. See {Six}.]
   Pertaining to, or designating, the number sixty; poceeding by
   sixties; sixty years old.
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   {Sexagenary arithmetic}. See under {Sexagesimal}.

   {Sexagenary scale}, or {Sexagesimal scale} (Math.), a scale
      of numbers in which the modulus is sixty. It is used in
      treating the divisions of the circle.
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Sexagesimal \Sex`a*ges"i*mal\, a. [Cf. F. sexag['e]simal.]
   Pertaining to, or founded on, the number sixty.
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   {Sexagesimal fractions} or {Sexagesimal numbers} (Arith. &
      Alg.), those fractions whose denominators are some power
      of sixty; as, 1/60, 1/3600, 1/216000; -- called also
      {astronomical fractions}, because formerly there were no
      others used in astronomical calculations.

   {Sexagesimal arithmetic}, or {Sexagenary arithmetic}, the
      method of computing by the sexagenary scale, or by
      sixties.

   {Sexagesimal scale} (Math.), the sexagenary scale.
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