[1] : The Collaborative International Dictionary of English v.0.48

efficacious \ef`fica"cious\, a. l. eficax, -acis, fr.
   efficere. see effect, n.
   possessing the quality of being effective; productive of, or
   powerful to produce, the effect intended; as, an efficacious
   law.

   syn: see effectual. -- ef`fica"ciously, adv.
        1913 webster
see also:
effect effectual ef`fica"ciously 

[2] : WordNet (r) 2.0

efficaciously
     adv : in an effective manner; "these are real problems that can be
           dealt with most effectively by rational discussion"
           syn: effectively ant: inefficaciously, inefficaciously
see also:
effectively inefficaciously 

Efficaciously >> E Words
Efficaciously, definition of term: Efficaciously
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