effectual effectual /ɪˈfektʃʊəl/

adjective

1. Producing or capable of producing an intended result or having a striking effect  ( effectual , efficacious , effective )
   producing or capable of producing an intended result or having a striking effect
    An air-cooled motor was more effective than a witch's broomstick for rapid long-distance transportation
   an air-cooled motor was more effective than a witch's broomstick for rapid long-distance transportation
    Effective teaching methods
   effective teaching methods
    Effective steps toward peace
   effective steps toward peace
    Made an effective entrance
   made an effective entrance
    His complaint proved to be effectual in bringing action
   his complaint proved to be effectual in bringing action
    An efficacious law
   an efficacious law
   
2. Having legal efficacy or force  ( effectual , sound , legal )
   having legal efficacy or force
    A sound title to the property
   a sound title to the property