Lewis & Short

băcillum, i, n. (băcillus, i, m., Isid. Orig. 20, 13, 1) dim. [baculus],

  1. I. a small staff, a wand, Cic. Fin. 2, 11, 33; id. Div. 1, 17, 30 dub.; Varr. R. R. 1, 50, 2; Juv. 3, 28.
  2. II. Esp., the wand or staff of the lictor: anteibant lictores, non cum bacillis, sed cum fascibus, Cic. Agr. 2, 34, 93.