nox·​ious | \ ˈnäk-shəs How to pronounce noxious (audio) \

Definition of noxious

1a : 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

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Other Words from noxious

noxiously adverb
noxiousness noun

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 Avoiding noxious gasoline, this cordless chainsaw comes with a G-Max 40V rechargeable lithium-ion battery that can be swapped and shared with other Greenworks yard work tools. Popular Science, "Great chainsaws for every job, from trims to demolitions," 15 Apr. 2020 Not surprisingly, the control flies avoided the noxious solution and slurped up the other one. Mitch Leslie, Science | AAAS, "Proteins that sense light also sense taste, at least in fruit flies," 2 Apr. 2020 Why it is now called a 'noxious plant' Stinknet plants can grow up to 2 feet high and tend to fill in open spaces between native plants. Debra Utacia Krol, azcentral, "It may look like a wildflower, but 'stinknet' is a menace to native plants and people," 26 Mar. 2020 Suddenly the idea of having a Council of Positive Male Role Models for my daughters went from being a quaint, inessential sidebar of my having cancer to an urgent necessity of growing up around noxious, outdated bro culture. Bruce Feiler, Los Angeles Times, "I lived my worst fear as a father. Here’s what I learned about surviving a crisis," 23 Mar. 2020 Eyes protected by goggles, breathing filtered air to protect his lungs, the 40-year-old multiple Guinness World Record holder vanished into clouds of noxious fumes and watery heat, his progress monitored on a split-screen thermal camera. Cydney Henderson, USA TODAY, "'Volcano Live!' Daredevil Nik Wallenda defies gravity, lava with wirewalk over volcano," 5 Mar. 2020 The smoke from the fires has blanketed parts of Indonesia, Singapore, Malaysia and southern Thailand in a noxious haze. San Diego Union-Tribune, "Haze from Indonesian fires now affecting Philippines," 20 Sep. 2019 The shrub, which displaces native plants with thickets impenetrable to wildlife, is a widespread noxious weed in the Pacific Northwest but is fairly new to New York. Washington Post, "Wags and weeds: Invasive plants meet match in detection dogs," 24 Aug. 2019 Although the noxious gas isn't thought to be a major contributor to climate change, studying its concentration in the atmosphere can help scientists understand other heat-trapping greenhouse gases that do drive global warming. NBC News, "Coronavirus shutdowns have unintended climate benefits: cleaner air, clearer water," 18 Mar. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'noxious.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of noxious

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

History and Etymology for noxious

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-.

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Time Traveler for noxious

Time Traveler

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

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Last Updated

1 May 2020

Cite this Entry

“Noxious.” Dictionary, Merriam-Webster, Accessed 2 Jun. 2020.

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More Definitions for noxious


How to pronounce noxious (audio)

English Language Learners Definition of noxious

formal : harmful to living things


nox·​ious | \ ˈnäk-shəs How to pronounce noxious (audio) \

Kids Definition of noxious

: causing harm noxious fumes


nox·​ious | \ ˈnäk-shəs How to pronounce noxious (audio) \

Medical Definition of noxious

: physically harmful or destructive to living beings noxious wastes

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More from Merriam-Webster on noxious

Thesaurus: All synonyms and antonyms for noxious

Spanish Central: Translation of noxious

Nglish: Translation of noxious for Spanish Speakers

Britannica English: Translation of noxious for Arabic Speakers

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