The Collaborative International Dictionary
astronomical fractions
Sexagesimal \Sex`a*ges"i*mal\, a. [Cf. F. sexag['e]simal.] Pertaining to, or founded on, the number sixty.
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.