Lewis & Short

dĕ-unx, uncis, m. [uncia], eleven twelfths, Varr. L. L. 5, § 172 Müll.: jugeri, Col. 5, 1, 12: heres ex deunce, Cic. Caecin. 6 fin.: avidi deunces, i. e. eleven per cent., Pers. 5, 150: potare deunces, i. e. eleven measures (cyathos), Mart. 12, 28; cf. id. 6, 78.