hazardous
HAZ-er-duhs
/ˈhæzərdəs/
Risky; dangerous; presenting a threat to health or safety.
Often used in legal and technical contexts (e.g., 'hazardous waste') to denote materials that pose specific, regulated risks to human health or the environment.
The story behind the word. The word 'hazardous' has a surprising origin in gambling. It comes from the Arabic 'al-zahr', which means 'the die' (as in dice). Crusaders brought the word back to Europe as 'hasard', a game of chance. Over centuries, the concept of 'chance' evolved into 'risk', and finally into 'danger'—giving us 'hazardous waste'.
Word relationships
- dangerous: Dangerous is a general term for anything that can cause harm, while hazardous is more formal and often refers to regulatory risks or chemical/environmental threats.
- perilous: Perilous is a literary term implying extreme, immediate danger (like a perilous journey), whereas hazardous is technical and systemic.
- safe: Safe means free from danger or risk.
- harmless: Harmless means incapable of causing any injury or damage.
Commonly confused with
- toxic: Toxic specifically means poisonous, while hazardous is broader and can include explosive, flammable, or radioactive dangers.
Word family
- hazard (noun): A danger or risk.
- hazardously (adverb): In a dangerous or risky manner.
Collocations
- hazardous waste
- hazardous materials
- hazardous conditions
- potentially hazardous
Example sentences
- "Chemical solvents and old batteries are classified as hazardous waste and must be handled carefully." A warning label on household chemicals.
- "The crew wore protective suits to remove the hazardous materials from the abandoned factory." An article about environmental cleanups.
Memory hook
Think of rolling a 'hazard' (die)—it is a risky game that could have dangerous consequences. Hazardous: A roll of the dice with your safety.
When not to use
Do not use 'hazardous' for minor inconveniences. It implies a serious, often toxic or physical danger.
Fun facts
- The 'Hazardous Materials' placard system used on trucks in the US uses specific colors and numbers to tell firefighters exactly what kind of danger (fire, poison, explosive) is inside.
Related words
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