Lewis & Short

callĭdĭtas, ātis, f. [callidus], the being callidus, in a good or bad sense.

  1. I. In a good sense, shrewdness, skill, skilfulness, readiness, aptness (so several times after the Aug. period): calliditas ingenii, Nep. Eum. 1, 3; Ov. F. 3, 380; Plin. 37, 12, 74, § 195; Tac. Agr. 9; Flor. 2, 17, 15; Cic. Har. Resp. 9, 19.
    Far more freq. and class.,
  2. II. In a bad sense, cunning, craft, slyness, artfulness: scientia, quae est remota ab justitiā, calliditas potius quam sapientia est appellanda, Cic. Off. 1, 19, 63; 3, 32, 113; id. Rosc. Com. 7, 20; id. Har. Resp. 9, 19; id. Or. 39, 137; Quint. 2, 5, 7; 4, 2, 126; Ov. H. 16, 300; 20, 126; Mart. 11, 50, 2 al.
    Of stratagem in war, Liv. 42, 47, 7: calliditas ad robur accesserat, Flor. 3, 4, 3.
    Trop., of oratorical artifice: genus ejusmodi calliditatis atque calumniae, Cic. Part. Or. 39, 137.
    In plur.: servi venere in mentem Syri Calliditates, Ter. Heaut. 5, 1, 14; Lact. 2, 12, 17.