Lewis & Short

exsŭpĕrābĭlis (exup-), e, adj. [exsupero].

  1. I. Pass., that may be overcome, surmountable, superable (poet.): non exsuperabile saxum (Sisyphi), Verg. G. 3, 39: ingenium mortale, Stat. Th. 1, 214.
  2. * II. Act., that overcomes, overpowering, irresistible: opera, Quadrig. ap. Gell. 17, 2, 14.