Quadrivia, derived from the Latin term "quadrivium," refers to the branches of study that were taught in medieval universities - arithmetic, geometry, music, and astronomy. While quadrivia remains an uncommon term in modern vocabulary, synonyms can be used in its place to refer to the four subjects studied in medieval universities. Mathematics is one of the synonyms for arithmetic while trigonometry or algebra can be used in place of geometry. Harmonics or musical theory can be used as synonyms for music, while astrology or astrophysics can be used for astronomy. These synonyms allow for clearer communication when discussing the subjects that were studied in medieval universities.