quā^drĭvĭum

I. Lit., a place where four ways meet, a crossway, cross-road: in quadriviis et angiportis, Cat. 58, 4; so Juv. 1, 63: DII, Inscr. Grut. 84, 5; 1015, 1; Inscr. Rein. col. 1, n. 14.—

II. Transf., the assemblage of the four mathematical sciences (arithmetic, music, geometry, and astronomy), Boëth. Arithmet. 1, 1.