sexagenary
  (a.)六十的
  Sex·ag·e·na·ry a.  Pertaining to, or designating, the number sixty; poceeding by sixties; sixty years old.
  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.
  Sex·ag·e·na·ry, n.
  1. Something composed of sixty parts or divisions.
  2. A sexagenarian.
  ◄ ►