effectual

Adjective

• having legal efficacy or force
  • a sound title to the property
    

• 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-LewisMumford
    
  • effective teaching methods
    
  • effective steps toward peace
    
  • made an effective entrance
    
  • his complaint proved to be effectual in bringing action
    
  • an efficacious law
    

Related words

• Synonyms: 
  legal , sound , effective , efficacious
• Antonyms: 
  ineffective , uneffective , ineffectual