noxious

adjective

nox·​ious ˈnäk-shəs How to pronounce noxious (audio)
Synonyms of noxiousnext
1
a
: physically harmful or destructive to living beings
noxious waste
noxious fumes
b
: constituting a harmful influence on mind or behavior
especially : morally corrupting
noxious doctrines
2
: disagreeable, obnoxious
this noxious political scandal—H. L. Ickes
noxiously adverb
noxiousness noun

Synonyms

See all Synonyms & Antonyms in Thesaurus 
Choose the Right Synonym for noxious

pernicious, baneful, noxious, deleterious, detrimental mean exceedingly harmful.

pernicious implies irreparable harm done through evil or insidious corrupting or undermining.

the claim that pornography has a pernicious effect on society

baneful implies injury through poisoning or destroying.

the baneful notion that discipline destroys creativity

noxious applies to what is both offensive and injurious to the health of a body or mind.

noxious chemical fumes

deleterious applies to what has an often unsuspected harmful effect.

a diet found to have deleterious effects

detrimental implies obvious harmfulness to something specified.

the detrimental effects of excessive drinking

Examples of noxious in a Sentence

mixing bleach and ammonia can cause noxious fumes that can seriously harm you noxious smog that for years has been encrusting the historic cathedral with soot
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In addition to preventing material damage, Wildfire Shield prevents the ill effects of noxious smoke. —Alison Van Houten, TIME, 30 Oct. 2024 Meanwhile, noxious chemicals from the eruptions or even an uptick in ultraviolet radiation from ozone-destroying chemicals injected into the stratosphere could all have played a role. —Bypaul Voosen, science.org, 12 Sep. 2024 Little was known of the noxious nature of the fish until this research came out. —Scott Travers, Forbes, 24 Oct. 2024 The suit claims the lagoon is the source of a noxious fumes and odors and resulted in economic loss to Spinas, according to a news release issued by the attorneys. —Randal Seyler, arkansasonline.com, 21 Oct. 2024 See all Example Sentences for noxious 

Word History

Etymology

Middle English noxius, borrowed from Latin noxius "guilty, delinquent, harmful, injurious" (derivative of noxa "injurious behavior, harm, mischief") + -us -ous; noxa derivative (perhaps with -s- as a desiderative suffix) from the base of nocēre "to damage (things), injure, harm (persons)," going back to Indo-European *noḱ-éi̯e- "destroy" (with semantic weakening in Latin), whence also Sanskrit nāśáyati "(s/he) destroys," causative derivatives from a verbal base *neḱ- "disappear, pass out of existence, perish," whence, with varying ablaut grades, Sanskrit náśyati "(s/he) is lost, perishes," Avestan nąsat̰ "has gone away, is lost," Tocharian B näk- "destroy," (in middle voice) "disappear, be destroyed"

Note: The Indo-European verbal base *neḱ- is also the source of a root noun attested as Latin nec-, nex "violent death, killing"; see necro-.

First Known Use

15th century, in the meaning defined at sense 1a

Time Traveler
The first known use of noxious was in the 15th century

Dictionary Entries Near noxious

noxal surrender

noxious

noyade

See More Nearby Entries 

Cite this Entry

“Noxious.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/noxious. Accessed 28 Nov. 2024.

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Kids Definition

noxious

adjective
nox·​ious ˈnäk-shəs How to pronounce noxious (audio)
: harmful especially to health : unwholesome
noxious fumes

Medical Definition

noxious

adjective
nox·​ious ˈnäk-shəs How to pronounce noxious (audio)
: physically harmful or destructive to living beings
noxious wastes

More from Merriam-Webster on noxious

Nglish: Translation of noxious for Spanish Speakers

Britannica English: Translation of noxious for Arabic Speakers

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