Lewis & Short

2. arbī̆trātus, ūs, m. [arbitror].

  1. I. The judgment (as will, not as opinion; accordingly = voluntas, not = sententia), freewill, inclination, pleasure, wish, choice, decision (class.; cf. Gell. 13, 20, 19: hic allegatus et hic arbitratus pro allegatione proque arbitratione dicuntur. Quā ratione servatā arbitratu et allegatu meo dicimus, which latter expression is most freq. used): viri boni arbitratu resolvetur, Cato, R. R. 149, 2; so id. ib. 145, 3: arbitratu domini, id. ib. 144, 1: nunc quidem meo arbitratu loquar libere, quae volam et quae lubebit, Plaut. Truc. 2, 1, 2: Vapulabis meo arbitratu et novorum aedilium, id. Trin. 4, 2, 148; so id. Capt. 3, 1, 35; id. Ep. 5, 2, 22; id. Men. 5, 5, 46; id. Mil. 4, 6, 6; id. Ps. 1, 5, 13: tuus arbitratus sit: comburas, si velis, id. As. 4, 1, 21; so id. Rud. 5, 2, 68: Er. Agedum, excutedum pallium. St. Tuo arbitratu, id. Aul. 4, 4, 20; id. Am. 3, 2, 50; id. Most. 3, 2, 106; id. Capt. 4, 2, 87; id. Ps. 2, 2, 66; id. Truc. 5, 19: quas (sententias) exposui arbitratu meo, Cic. Lael. 1, 3: ut id meo arbitratu facerem, id. Fin. 1, 21, 72, and id. ib. 4, 1, 2; id. Fam. 7, 1, 5: tuo vero id quidem arbitratu, id. Fin. 1, 8, 28; so id. Brut. 11, 42; Tac. Or. 42 fin.: suo arbitratu, Plaut. Men. 1, 1, 15: ejus arbitratu fieri, id. Rud. 4, 3, 96: arbitratu suo, Suet. Tib. 68: Tr. Quoius arbitratu nos vis facere? Gr. Viduli arbitratu, Plaut. Rud. 4, 3, 63 sq.; 4, 3, 66: senatūs arbitratu, Suet. Tib. 34; so id. Aug. 35.
  2. II. Direction, guidance: considerare oportet, cujus arbitratu sit educatus, Cic. Inv. 1, 25; so Inscr. Grut. 185, 2.