Lewis & Short

ăbĕcĕdārĭus, a, um [a, b, c, d], belonging to the alphabet, alphabetical (late Lat.).

  1. I. Adj.: psalmi, Aug. Retract. 1, 20.
  2. II. Subst.
    1. A. ăbĕcĕdāĭus, ĭi, m., one who learns the a, b, c (eccl. Lat.).
    2. B. ăbĕcĕdārĭa, ae, f., elementary instruction, Fulg. Myth. 3, 10.
    3. C. ăbĕ-cĕdārĭum, ĭi, n., a, b, c, the alphabet (eccl. Lat.).