Lewis & Short

ŏbĕlus, i, m., = ὀβελός (a spit), a critical mark shaped like a spit (†), placed opposite suspected passages in books, an obelisk (late Lat.), Hier. Ep. 104; 108; 112; Aus. Sap. 13 prooem.; Isid. Orig. 1, 20, 2.