hazardous
adjective
haz·ard·ous
ˈha-zər-dəs 
1
: involving or exposing one to risk (as of loss or harm)
a hazardous occupation
disposing of hazardous waste
2
: depending on the effect of unpredictable and unanalyzable forces in determining events : depending on hazard (see hazard entry 1 sense 2a) or chance
hazardous outcomes
hazardously
adverb
hazardousness
noun
Examples of hazardous in a Sentence
It was a hazardous voyage.
These are hazardous chemicals that can cause death if inhaled.
Recent Examples on the Web
However, a small portion of them, known as potentially hazardous asteroids (PHAs), do require closer tracking.
—
Soo Kim, MSNBC Newsweek, 23 Sep. 2025
Several of Colorado’s high-elevation mountain passes could see hazardous conditions and up to 5 inches of snow between Monday and Wednesday, according to the National Weather Service.
—Lauren Penington, Denver Post, 22 Sep. 2025
Sylvia said hazardous materials crews have since completed their work.
—Darrell Smith, Sacbee.com, 22 Sep. 2025
There is low probability that widespread hazardous weather will occur during the rest of the week, the statement reads.
—Bebe Hodges, Cincinnati Enquirer, 22 Sep. 2025
See All Example Sentences for hazardous
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Soo Kim, MSNBC Newsweek, 23 Sep. 2025
Several of Colorado’s high-elevation mountain passes could see hazardous conditions and up to 5 inches of snow between Monday and Wednesday, according to the National Weather Service.
—Lauren Penington, Denver Post, 22 Sep. 2025
Sylvia said hazardous materials crews have since completed their work.
—Darrell Smith, Sacbee.com, 22 Sep. 2025
There is low probability that widespread hazardous weather will occur during the rest of the week, the statement reads.
—Bebe Hodges, Cincinnati Enquirer, 22 Sep. 2025
See All Example Sentences for hazardous
Cite this Entry
“Hazardous.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hazardous. Accessed 26 Sep. 2025.
Copy CitationKids Definition
hazardous
adjective
haz·ard·ous
ˈhaz-ərd-əs
hazardously
adverb
hazardousness
noun
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