Lewis & Short

mensūrālis, e, adj. [mensura], of or belonging to measuring, measuring- (post-class.): mensuralis linea, Sicul. Fl. p. 19 Goes.
Plur. as subst.: mensūrālia, ium, n., the title of a work by Varro, Prisc. p. 817 P.
Hence, adv.: mensūrālĭter, by measure (post-class.), Hyg. de Limit. p. 167 Goes.