Lewis Short
dē-dĕcŏrōsus, a, um
* Adj., disgraceful, dishonorable (post-Aug., and very rare): nex,Aur. Vict. Epit. 39 fin.—Comp., Hier. in Jes. 16, 58, 10.—Adv.: dēdĕcŏ-rōse, disgracefully: vixi, turpius peream, Nero ap. Aur. Vict. Epit. 5 fin.
Charlton T. Lewis, Charles Short, A Latin Dictionary