Tetartemorion, rij, neut. gen. The fourth part of the Zodiake circle, wherein are the xii signes. It is also that, which Astronomers call the quadrate aspecte of the planets.
Lewis and Short: Latin dictionary
tĕtartēmŏrĭa, ae, f., = tetarthmopi/a,a fourth in music, Mart. Cap. 9, 930 and 959.