Source : Webster's Revised Unabridged Dictionary (1913)

Effectual \Ef*fec"tu*al\ (?; 135), a. [See {Effect}, n.]
   Producing, or having adequate power or force to produce, an
   intended effect; adequate; efficient; operative; decisive.
   --Shak.

         Effectual steps for the suppression of the rebellion.
                                                  --Macaulay.

   {Effectual calling} (Theol.), a doctrine concerning the work
      of the Holy Spirit in producing conviction of sin and
      acceptance of salvation by Christ, -- one of the five
      points of Calvinism. See {Calvinism}.

   Syn: {Effectual}, {Efficacious}, {Effective}.

   Usage: An efficacious remedy is had recourse to, and proves
          effective if it does decided good, effectual if it
          does all the good desired. --C. J. Smith.