Perfidious and Unfaltering

Opposite meaning words

Perfidious adjective - Not true in one's allegiance to someone or something.

Usage example: a perfidious campaign worker revealed the senator's strategy to his leading rival for the nomination

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Unfaltering is an antonym for perfidious.

Nearby Words: perfidy, perfidiously

Unfaltering adjective - Marked by firm determination or resolution; not shakable.

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Perfidious is an antonym for unfaltering.

Nearby Word: unfalteringly

Cite this Source

Unfaltering and Perfidious. (2016). Retrieved 2026, August 15, from https://thesaurus.plus/related/perfidious/unfaltering

Perfidious & Unfaltering. N.p., 2016. Web. 15 Aug. 2026. <https://thesaurus.plus/related/perfidious/unfaltering>.

Unfaltering or Perfidious. 2016. Accessed August 15, 2026. https://thesaurus.plus/related/perfidious/unfaltering.

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