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Synonyms

hazardous

American  
[haz-er-duhs] / ˈhæz ər dəs /

adjective

  1. full of risk; perilous; risky.

    a hazardous journey.

    Synonyms:
    unsafe, dangerous
    Antonyms:
    secure, safe
  2. dependent on chance.

    Synonyms:
    speculative, risky, uncertain, chancy
    Antonyms:
    sure, reliable, certain

hazardous British  
/ ˈhæzədəs /

adjective

  1. involving great risk

  2. depending on chance

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

  • hazardously adverb
  • hazardousness noun
  • nonhazardous adjective
  • nonhazardously adverb
  • nonhazardousness noun
  • ultrahazardous adjective
  • unhazardous adjective
  • unhazardously adverb

Etymology

Origin of hazardous

First recorded in 1570–80; hazard + -ous

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

FBI agents and hazardous materials teams descended on a gated residential community in Irvine on Wednesday night, performing a raid on a single-family home and carefully removing chemicals found inside.

From Los Angeles Times

Around 880 tonnes of hazardous material remain inside the power station, the site of one of the world's worst nuclear accidents after a tsunami was triggered by a 9.0-magnitude earthquake.

From Barron's

The hazardous and snowy conditions also led to serious flight disruptions on Monday and Tuesday.

From BBC

"I am asking all New Yorkers to stay inside and stay off the roads for your safety," he said, adding that the city's Monday morning commute "will be extremely hazardous."

From Barron's

The extraction of the victims stalled on Thursday due to hazardous weather conditions, the Nevada County Sheriff's Office, which is leading the search, said on Thursday.

From BBC