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
efficacious (adj.)
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;
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