Ef·fi·ca·cious a. Possessing the quality of being effective; productive of, or powerful to produce, the effect intended; as, an efficacious law.
Syn: -- See Effectual.
-- Ef*fi*ca*cious*ly, adv.
adj 1: marked by qualities giving the power to produce an intended
effect; "written propaganda is less efficacious than
the habits and prejudices...of the readers"-Aldous
Huxley; "the medicine is efficacious in stopping a
cough" [ant: inefficacious]
2: 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" [syn:
effective, effectual] [ant: ineffective]