redoubtable redoubtable /rəˈdaʊtəbəl/

adjective

1. () Inspiring fear  ( unnerving , doubtable [Archaic] , redoubtable , formidable )
   inspiring fear
    The formidable prospect of major surgery
   the formidable prospect of major surgery
    A tougher and more redoubtable adversary than the heel-clicking, jackbooted fanatic
   a tougher and more redoubtable adversary than the heel-clicking, jackbooted fanatic
    Something unnerving and prisonlike about high grey wall
   something unnerving and prisonlike about high grey wall
   
2. Worthy of respect or honor  ( redoubtable )
   worthy of respect or honor
    Born of a redoubtable family
   born of a redoubtable family