Lewis & Short

centēsĭmus, a, um,

  1. I. num. ordin. [centum], the hundredth: pars, Plaut. Mil. 3, 1, 166: lux ab interitu Clodii, Cic. Mil. 35, 98 al.
    1. B. Subst.: centēsĭma, ae, f. (sc. pars), the hundredth part of a thing, as a revenue, tax, a percentage: rerum venalium, Tac. A. 1, 78; cf. id. ib. 2, 42.
      And of interest, 1 per cent. monthly; therefore, acc. to our manner of computing interest, 12 per cent. annually, Cic. Att. 5, 21, 11 sq.; Sen. Ben. 7, 10: binae, Cic. Verr. 2, 3, 70, § 165.
  2. II. For centuplex, a hundredfold: frux, Plin. 5, 4, 3, § 24: grano, id. 18, 16, 40, § 141; cf. Varr. R. R. 1, 44, 2.