Lewis Short
(adjective) : dŭcālis, e, dux
* Of or belonging to a leader or commander (post-class.): tunicae, Valer. Imp. ap. Vop. Aurel. 13.—Adv.: dŭcālĭter, like a leader or general: antecedere,Sid. Ep. 5, 13.—Comp., Sid. Ep. 8, 6.
Charlton T. Lewis, Charles Short, A Latin Dictionary