quadrivium

WordNet 3.6
 n quadrivium (Middle Ages) a higher division of the curriculum in a medieval university involving arithmetic and music and geometry and astronomy
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Webster's Revised Unabridged Dictionary

 n Quadrivium The four “liberal arts,” arithmetic, music, geometry, and astronomy;  so called by the schoolmen. See Trivium.
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Century Dictionary and Cyclopedia

 n quadrivium The collective name of the four branches of mathematics according to the Pythagoreans—arithmetic (treating of number in itself), music (treating of applied number), geometry (treating of stationary number), and astronomy (treating of number in motion). This Pythagorean quadrivium, preceded by the trivium of grammar, logic, and rhetoric, made up the seven liberal arts taught in the schools of the Roman empire.
 n quadrivium A place where four ways meet.
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Chambers's Twentieth Century Dictionary

 n Quadrivium kwodriv′ium the Pythagorean name for the four branches of mathematics—arithmetic, music, geometry, astronomy—when preceded by the trivium of grammar, logic, and rhetoric—together making up the seven liberal arts taught in the schools of the Roman Empire
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Webster's Revised Unabridged Dictionary
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Chambers's Twentieth Century Dictionary
L., 'the place where four roads meet'—L. quatuor, four, via, a way.
In literature:
Likewise, some work on Astronomy, which was one of the quadrivium subjects.
"Practical Essays" by Alexander Bain
Such men as Anselm were educated on the Trivium and Quadrivium.
"The History of Dartmouth College" by Baxter Perry Smith
The Quadrivium or Music, Arithmetic, Geometry and Astronomy, was relegated to the Universities and only pursued by very few.
"A History of Giggleswick School" by Edward Allen Bell
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