Effectual and Inefficacious

Opposite meaning words

Effectual adjective - Producing or capable of producing an intended result or having a striking effect.

Usage example: his complaint proved to be effectual in bringing action

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Inefficacious is an antonym for effectual.

Inefficacious adjective - Not producing the desired result.

Usage example: his efforts to restore the neglected houseplant back to health were belated and sadly inefficacious

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Effectual is an antonym for inefficacious.

Cite this Source

Inefficacious and Effectual. (2016). Retrieved 2026, August 16, from https://thesaurus.plus/related/effectual/inefficacious

Effectual & Inefficacious. N.p., 2016. Web. 16 Aug. 2026. <https://thesaurus.plus/related/effectual/inefficacious>.

Inefficacious or Effectual. 2016. Accessed August 16, 2026. https://thesaurus.plus/related/effectual/inefficacious.

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