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
Example Sentences
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 WebNear-record amounts of seaweed are smothering Caribbean coasts from Puerto Rico to Barbados, killing fish and other wildlife, choking tourism and releasing stinky, noxious gases.Fox News, 4 Aug. 2022 Near-record amounts of seaweed are smothering Caribbean coasts from Puerto Rico to Barbados, killing fish and other wildlife, choking tourism and releasing stinky, noxious gases. Dánica Coto, Anchorage Daily News, 3 Aug. 2022 Letting nature take its course is an option but noxious gases that naturally build up can prove dangerous. Heather Chen, CNN, 23 May 2022 Large quantities of dry chemicals are needed to smother lithium ion battery fires, which burn hotter and release noxious gases in the process. Aurora Almendral, Quartz, 21 Feb. 2022 Firefighters tested the air quality inside the home and found no noxious gases, but that was after other emergency personnel had been in and out, opening doors, which could have caused any existing gas to dissipate, an official said. Charles Trepany, USA TODAY, 26 Jan. 2022 According to Telegram & Gazette, authorities at the scene found no signs of noxious gases and did not suspect apparent trauma had occurred. Dory Jackson, PEOPLE.com, 25 Jan. 2022 But people were warned to stay away because of the risk from noxious fumes and hot magma. Morgan Coates, Washington Post, 3 Aug. 2022 The burn pits emitted noxious fumes that researchers have shown can lead to health problems, including neurological issues and lung cancer. Ben Kesling, WSJ, 16 June 2022 See More
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-.