English to English

noun (n)

• power to be effective; the quality of being able to bring about an effect

  kekuatan untuk lebih berkesan; kualitas mampu membawa tentang efek

  Synonym:
  effectiveness, effectivity, effectuality
  Antonym:
  ineffectiveness, ineffectuality, ineffectualness
  

  source: wordnet30
• The quality of being effectual.

  kualitas yang tepat jitu.

  source: webster1913