noxious

American  

[nok-shuhs] / ˈnɒk ʃəs /

adjective

1. harmful or injurious to health or physical well-being.

   noxious fumes.

   Synonyms:

   deleterious, detrimental, nocuous, unhealthy, unwholesome, hurtful

   Antonyms:

   harmless

2. morally harmful; corrupting; pernicious.

   a noxious plan to spread dissension.

   Synonyms:

   corruptive

   Antonyms:

   harmless

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noxious British  

/ ˈnɒkʃəs /

adjective

1. poisonous or harmful

2. harmful to the mind or morals; corrupting

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Other Word Forms

• noxiously
  adverb
• noxiousness
  noun

Etymology

Origin of noxious

1605–15; < Latin noxius harmful, hurtful, injurious, equivalent to nox ( a ) harm, hurt, injury (akin to nocēre to do harm, inflict injury; see innocent) + -ius -ious

Explanation

Something noxious is harmful and could be even fatal — whether it is colorless, odorless, and invisible like carbon monoxide, or dark, strong-smelling, and obvious, like black smoke from a fire. People are called noxious too when they hurt others with cruelty or mental anguish. English and Latin roots for noxious are related to the meanings of "harm," "damage," and "injury." While obnoxious might come to mind when seeing the word noxious, obnoxious is a much less damaging adjective to describe someone annoying. Most uses for noxious involve real physical or emotional damage unless the word is used in exaggeration. Examples range from "the noxious gas fumes made the dog pass out" to "his cologne was so noxious I had to exit the elevator and take the stairs."

Example Sentences

Noxious to livestock and native plants, the plant was introduced in the United States in 1822 and is found widely here.

From Science Daily • Mar. 6, 2024

Noxious stories about the value of suffering and a lifetime of scrounging exist to convince ourselves of the false idea that a passion cannot be a profession.

From New York Times • Jul. 6, 2022

King County spends around $4 million a year trying to control these invasive plants as part of the King County Noxious Weed Control Program.

From Seattle Times • Jun. 11, 2022

Noxious fumes filled the room as white globs of melted plastic dripped down onto the wood, catching it on fire.

From Los Angeles Times • Jan. 29, 2022

Noxious clouds expanded around the giant, filling the ruins like thick cigar smoke.

From "Blood of Olympus" by Rick Riordan

Related Words

• corrupting
• destructive
• fetid
• harmful
• pernicious
• poisonous
• putrid
• toxic
• unhealthy
• virulent