Lewis & Short

bĕnĕfĭcus (better than bĕnĭfĭcus), a, um, adj. [bene-facio] (comp. and sup. regularly formed, beneficentior, Sen. Ben. 1, 4, 5; 5, 9, 2: beneficentissimus, Cic. Lael. 14, 51; id. N. D. 2, 25, 64; ante-class. beneficissimus, Cato ap. Prisc. p. 603 P.), generous, liberal, beneficent, obliging, favorable (rare but class.): de Ptolemaeo rege optimo et beneficissimo, Cato, l. l.: beneficum esse oratione, Plaut. Ep. 1, 2, 14: ubi beneficus, si nemo alterius causā benigne facit? Cic. Leg. 1, 18, 49: in amicum, id. Off. 1, 14, 42; 1, 14, 44: sunt enim benefici generique hominum amici, id. Div. 2, 49, 102: beneficus, salutaris, mansuetus civis, id. Mil. 8, 20; id. Lael. 9, 31; cf. Gell. 17, 5, 4: actio, Sen. Ben. 2, 34, 5.
* Adv.: bĕnĕfĭcē, beneficently: facere, Gell. 17, 5, 13.