Deleterious and Harmless

Opposite meaning words

Deleterious adjective - Causing or capable of causing harm.

Usage example: nicotine has long been recognized as a deleterious substance

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Harmless is an antonym for deleterious.

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

Usage example: a perfectly harmless little spider

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Deleterious is an antonym for harmless.

Nearby Words: harm, harmful, harmlessly

Cite this Source

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

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

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

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