Firm and Unsound

Opposite meaning words

Firm adjective - Marked by the ability to withstand stress without structural damage or distortion.

Usage example: built on a firm foundation, so the house hasn't settled

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Unsound is an antonym for firm.

Nearby Words: firming, firmness, firmly, firmed

Unsound adjective - Having or showing a very abnormal or sick state of mind.

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Firm is an antonym for unsound in flimsy topic.

Nearby Words: unsounded, unsoundly

Cite this Source

Unsound and Firm. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/firm/unsound

Firm & Unsound. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/firm/unsound>.

Unsound or Firm. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/firm/unsound.

Google Ngram Viewer shows how "firm" and "unsound" have occurred on timeline