quadrivium

n. four disciplines that comprised the advanced division of university studies during the Middle Ages (arithmetic, geometry, music, and astronomy)

The quadrivium comprised the four subjects, or arts, taught in medieval universities after the trivium. The word is Latin, meaning "the four ways" or "the four roads": the completion of the liberal arts.At many medieval universities, this would have been the course leading to the degree of Master of Arts (after the BA). After the MA the student could enter for Bachelor's degrees of the higher faculties, such as Music. To this day some of the postgraduate degree courses lead to the degree of Bachelor (the B.Phil and B.Litt degrees are examples in the field of philosophy, and the B.Mus remains a postgraduate qualification at Oxford and Cambridge universities).
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n. quadrivium, four disciplines that comprised the advanced division of university studies during the Middle Ages (arithmetic, geometry, music, and astronomy)

(n.)
The four "liberal arts," arithmetic, music, geometry, and astronomy; -- so called by the schoolmen. See Trivium.
  

Quadrivium (Latin) [from quattuor four + via path] A place where four roads meet and cross; used by Boethius and medieval scholars to denote the higher division of the seven liberal arts: arithmetic, geometry, music, and astronomy; the lower division, or trivium, consists of grammar, logic, and rhetoric.