noun

• Execution; performance; realization; operation.
  "The new law will come into effect on the first day of next year."
• (cinematography, computer graphics, demoscene) An illusion produced by technical means (as in "special effect")
  "The effect of flying was most convincing."
• (sound engineering) An alteration, or device for producing an alteration, in sound after it has been produced by an instrument.
  "I use an echo effect here to make the sound more mysterious."
• (sciences) A scientific phenomenon, usually named after its discoverer.
  "Doppler effect"

verb

• (transitive) To make or bring about; to implement.
  "The best way to effect change is to work with existing stakeholders."