Lewis Short
(adjective) : nūgax, ācis (collat. form indecl. ‡ nugas, σαπρός, Gloss. Philox.; so, ‡ nugas, inutilis, Gloss. Vet.; cf. Don. p. 1749 P.; Charis. p. 1; 15; 22; 120 ib.; Diom. p. 286 P.; Prisc. p. 649; 701 ib.; Val. Prob. 1464 and 1478 ib.), nugor
* Jesting, trifling, frivolous, Varr. ap. Non. 355, 22: qui tam nugax esset, Cael. ap. Cic. Fam. 8, 15, 1: nugax es,Petr. 52; Ambros. Ep. 58, 6ext.— Adv. only sup.: nūgācissimē (-sŭmē), in the most trifling manner, Plaut. Trin. 3, 3, 90.
Charlton T. Lewis, Charles Short, A Latin Dictionary