Harmless and Insidious

Opposite meaning words

Harmless adjective - Not causing or being capable of causing injury or hurt.

Usage example: a perfectly harmless little spider

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Insidious is an antonym for harmless.

Nearby Words: harm, harmful, harmlessly

Insidious adjective - Working or spreading in a hidden and usually injurious way.

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Harmless is an antonym for insidious in stealthy topic.

Nearby Word: insidiously

Cite this Source

Insidious and Harmless. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/harmless/insidious

Harmless & Insidious. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/harmless/insidious>.

Insidious or Harmless. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/harmless/insidious.

Google Ngram Viewer shows how "harmless" and "insidious" have occurred on timeline