Lewis & Short

prŏbābĭlis, e, adj. [probo].

  1. I. Lit., that may be assumed, believed, or proved; likely, credible, probable (class.): probabile est id, quod fere fieri solet, aut quod in opinione positum est, aut quod habet in se ad haec quandam similitudinem, sive id falsum est, sive verum, Cic. Inv. 1, 29, 46: quae probabilia videantur, id. Fin. 5, 26, 76: est enim in his rebus aliquid probabile, id. ib. 3, 17, 58; id. Ac. 2, 11, 33; 2, 63, 154: nihil est tam incredibile, quod non dicendo fiat probabile, id. Par. praef. 1: ratio, id. Off. 1, 3, 8: conjectura et ratio, id. Div. 2, 6, 16: probabilis et prope vera disputatio, id. de Or. 1, 56, 240: causa, id. Verr. 2, 5, 67, § 173: mendacium, Liv. 40, 29: Causae, Tac. A. 6, 14.
  2. II. Transf., in gen., worthy of approval, pleasing, agreeable, acceptable, commendable, laudable, good, fit (class.).
    1. A. Of persons: C. Licinius probabilis orator: jam vero etiam probatus, Cic. Brut. 76, 263: voce peracutā atque magnā, nec alia re ulla probabilis, id. ib. 68, 241: discipulus, id. de Or. 1, 28, 129: jucundior et probabilior populo orator, id. ib. 2, 36, 153; Nep. Cat. 3, 1.
    2. B. Of things concr. and abstr.: materia, Cic. Fam. 3, 6, 18: nomen, id. Caec. 25, 71: boves non minus probabiles animis, quam corporibus, Col. 6, 1, 2: aqua maxime probabilis, Plin. 31, 3, 23, § 38: gustus, Col. 3, 2, 24: soli et caeli qualitas, id. ib. 3, 1, 10: rosa nec odore, nec specie probabilis, Plin. 21, 4, 10, § 18: genus orationis, Cic. Part. 6, 19; Liv. 2, 13: mores, Col. 6, 2, 14: vir ingenio sane probabili, Cic. Brut. 48, 180.
      Hence, adv.: prŏ-bābĭlĭter.
    1. A. Probably, credibly (class.): rem breviter exponere et probabiliter, Cic. Or. 35, 122: rationem reddere, id. Fin. 3, 17, 58: dicere, id. de Or. 2, 82, 337: multa probabiliter argumentatus, Liv. 33, 28: justius et probabilius accusare, Cic. Inv. 2, 46, 136: defendere, Liv. 42, 48.
    2. B. Laudably, fitly, well (post-Aug.): consulatum gerere, Vell. 2, 46, 4: eleganter et probabiliter hoc dictum est, Gell. 9, 16, 6: recte et probabiliter dici, id. 1, 16, 9.
      Comp.: probabilius Lutatius, Val. Max. 2, 8, 2.