Lewis & Short

dŭcālis, e, adj. [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.