decisive

Adjective

• forming or having the nature of a turning point or crisis
  • a critical point in the campaign
    
  • the critical test
    

• characterized by decision and firmness
  • an able and decisive young woman
    
  • we needed decisive leadership
    
  • she gave him a decisive answer
    

• unmistakable
  • had a decisive lead in the polls
    

• determining or having the power to determine an outcome
  • cast the decisive vote
    
  • two factors had a decisive influence