Lewis & Short

prae-vārus, a, um, adj., very irregular or unsteady (very rare).

  1. I. Lit.: venarum pulsus praevaros (al. praeclaros, i. e. certos, distinctos), App. Flor. p. 362, 17.
  2. II. Trop., very perverse: quid enim tam praevarum? Cic. Fragm. ap. Isid. Orig. 10, 233.