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efficacious
adjective
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How to pronounce efficacious:

Definition of efficacious:

efficacious (adjective):
producing the intended result
having the power to produce a desired effect
marked by qualities giving the power to produce an intended effect.

Synonyms for efficacious:

serviceablecompetentcapableproductivepowerfulusefulactiveefficientpotentsuccessful
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Antonyms for efficacious:

anticlimacticunableflimsyunavailingbadunbelievableinefficientill-fatedlimitedimplausible
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Other 5-syllable words like efficacious

Here are some other common words that have 5 syllables, like efficacious does.

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