hazardous
HAZ-er-duhs
/ˈhæzərdəs/
Risky or dangerous, especially to health or safety.
In waste management, it specifically denotes materials that are toxic, corrosive, ignitable, or reactive.
The story behind the word. This word has a surprisingly playful origin. It comes from the Old French 'hasard', which was a game of chance played with dice, itself likely named after the castle of Hasart in Palestine during the Crusades. Because a roll of the dice is entirely unpredictable, anything 'hazardous' became associated with extreme risk and danger.
Word relationships
- dangerous: Dangerous is a general term for anything that can cause harm, while hazardous often implies a specific, systemic risk or regulatory classification.
- perilous: Perilous is highly literary and implies extreme, immediate danger, whereas hazardous is more technical and systemic.
- harmless: Harmless means completely safe and incapable of causing injury, the opposite of hazardous.
Commonly confused with
- toxic: Toxic means poisonous to living things; hazardous is broader and includes things that are explosive, flammable, or corrosive.
Word family
- hazard (noun): A danger or risk.
- hazardously (adverb): In a dangerous manner.
Collocations
- hazardous waste
- hazardous materials
- hazardous conditions
- highly hazardous
Example sentences
- "Employees must wear protective suits and respirators when handling hazardous industrial chemicals." Workplace safety guidelines
- "The illegal dumping of hazardous waste has severely contaminated the local soil and groundwater." Environmental news report
Memory hook
HAZARDous is like a HAZARD in golf or a roll of the dice—pure risk. A roll of the dice.
When not to use
Do not use for minor inconveniences; it must imply genuine risk of harm or damage.
Fun facts
- The hazard symbol (the skull and crossbones) was originally used by pirates before being adopted globally for toxic and hazardous substances.
Related words
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