/
ˈɒbdjʊrət/
adj.
 stubbornly refusing to change one's opinion or course of action.
Derivative
- obduracy n.
  - obdurately adv.
  - obdurateness n.
 
Etymology
ME (orig. in the sense ‘impenitent’): from L. obduratus, past part. of obdurare, from ob- ‘in opposition’ + durare ‘harden’.