quadrivium
/kwɒˈdrɪvɪəm/noun
- historical a medieval university course involving the 'mathematical arts' of arithmetic, geometry, astronomy, and music〈史〉（中世纪大学里开设的）四艺（包括算术、几何、天文、音乐）。比较TRIVIUM.
词源
Latin， literally 'the place where four roads meet' （in late Latin 'the four branches of mathematics'）， from quadri- 'four'+via 'road'.