Efficacious and Otiose

Opposite meaning words

Efficacious adjective - Producing or capable of producing a desired result.

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Otiose is an antonym for efficacious.

Otiose adjective - Producing no results.

Usage example: since you haven't read the book, I suppose that it would be otiose to inquire what you thought of it

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Efficacious is an antonym for otiose.

Cite this Source

Otiose and Efficacious. (2016). Retrieved 2026, August 14, from https://thesaurus.plus/related/efficacious/otiose

Efficacious & Otiose. N.p., 2016. Web. 14 Aug. 2026. <https://thesaurus.plus/related/efficacious/otiose>.

Otiose or Efficacious. 2016. Accessed August 14, 2026. https://thesaurus.plus/related/efficacious/otiose.

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