Deleterious
Deleterious adjective - Causing or capable of causing harm.
Usage example: nicotine has long been recognized as a deleterious substance
Lethal and deleterious are semantically related. In some cases you can use "Lethal" instead an adjective "Deleterious".
Lethal
Lethal adjective - Likely to cause or capable of causing death.
Usage example: we were lucky that the snake's venom wasn't lethal, and our friend turned out to be all right
Deleterious and lethal are semantically related. Sometimes you can use "Deleterious" instead an adjective "Lethal".
Nearby Word: lethality
Mutual synonyms
Related pairs
Both words in one sentence
-
For a large macroscopic change to present itself in a living thing, a number — usually a large number — of genes have to be mutated in a specific pattern, with no severely deleterious or lethal mutations happening.
Source: Nuclear Nasty - Such mutations are overwhelmingly silent (cause no change in phenotype), deleterious (cause a reduction, sometimes drastic, in reproductive fitness), or lethal (cause the individual to die as an embryo, fetus, or infant).
Source: Nuclear Nasty
Cite this Source
Lethal and Deleterious. (2016). Retrieved 2026, July 21, from https://thesaurus.plus/related/deleterious/lethal
Deleterious & Lethal. N.p., 2016. Web. 21 Jul. 2026. <https://thesaurus.plus/related/deleterious/lethal>.
Lethal or Deleterious. 2016. Accessed July 21, 2026. https://thesaurus.plus/related/deleterious/lethal.
Google Ngram Viewer shows how "deleterious" and "lethal" have occurred on timeline