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hazardous

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adjective haz·ard·ous \ˈha-zər-dəs\

Definition of hazardous

  1. 1 :  depending on the effect of unpredictable and unanalyzable forces in determining events :  depending on hazard (see 1hazard 3a) or chance hazardous outcomes

  2. 2 :  involving or exposing one to risk (as of loss or harm) a hazardous occupation disposing of hazardous waste

hazardously

adverb

hazardousness

noun

See hazardous defined for English-language learners

See hazardous defined for kids

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Examples of hazardous in a Sentence

  1. It was a hazardous voyage.

  2. These are hazardous chemicals that can cause death if inhaled.

Origin and Etymology of hazardous

see 1hazard


First Known Use: 1585

hazardous Synonyms

Synonyms
grave, grievous, dangerous, jeopardizing, menacing, parlous, perilous, risky, serious, threatening, unhealthy, unsafe, venturesome
Antonyms
harmless, innocent, innocuous, nonhazardous, nonthreatening, safe, unthreatening
Related Words
dicey, insecure, precarious, treacherous, uncertain; ultrahazardous; chance, haphazard, random; distressing, sickening, unpleasant; ugly, wicked; adverse, bad, baleful, baneful, deleterious, detrimental, evil, harmful, hurtful, ill, inimical, injurious, malignant, nasty, noxious, pernicious, pestilent; deadly, deathly, destructive, dire, fatal, fateful, fell, killer, lethal, mortal, murderous
Near Antonyms
advantageous, beneficial, good; ultrasafe

Synonym Discussion of hazardous

dangerous, hazardous, precarious, perilous, risky mean bringing or involving the chance of loss or injury. dangerous applies to something that may cause harm or loss unless dealt with carefully. soldiers on a dangerous mission hazardous implies great and continuous risk of harm or failure. claims that smoking is hazardous to your health precarious suggests both insecurity and uncertainty. earned a precarious living by gambling perilous strongly implies the immediacy of danger. perilous mountain roads risky often applies to a known and accepted danger. shied away from risky investments

HAZARDOUS Defined for English Language Learners

hazardous

play
adjective haz·ard·ous \ˈha-zər-dəs\

Definition of hazardous for English Language Learners

  • : involving risk or danger

HAZARDOUS Defined for Kids

hazardous

play
adjective haz·ard·ous \ˈha-zər-dəs\

Definition of hazardous for Students

  1. :  dangerous 1 hazardous chemicals

Law Dictionary

hazardous

adjective haz·ard·ous

Legal Definition of hazardous

  1. :  creating a hazard :  involving or exposing one to risk (as of loss or harm) a hazardous occupation a hazardous substance

hazardously

adverb

Learn More about hazardous

  1. Thesaurus: All synonyms and antonyms for hazardous Spanish Central: Translation of hazardous Nglish: Translation of hazardous for Spanish speakers Britannica English: Translation of hazardous for Arabic speakers

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Examples: hazardous in a Sentence
Tip: Synonym Guide