non-hazardous
Word family
Synonym discussion
Sense: adjective/1
'Non-hazardous' is the formal, regulatory choice — you see it on product labels, waste-sorting bins, and workplace safety sheets. It signals a specific judgement, often backed by testing, that something will not cause physical, chemical, or environmental harm. 'Harmless' is the everyday equivalent and feels softer: a harmless joke, a harmless little snake. 'Safe' is the broadest of the four; it covers far more than chemical risk and reaches into emotional and situational safety (a safe neighbourhood, a safe choice). 'Non-toxic' is the narrowest — it focuses on poisoning risk only, so a paint can be non-toxic but still flammable, while 'non-hazardous' usually rules out the wider set of dangers. In a lab report you would write 'non-hazardous'; talking to your child, you would say 'safe'.
Common collocations
Etymology
Formed in English by adding the prefix 'non-' (meaning 'not') to 'hazardous'. 'Hazardous' itself reached English in the late 1500s, built from 'hazard' (originally a dice game) plus the adjective ending '-ous'. 'Hazard' traces back through Old French 'hasard' to an Arabic source connected to dice play. The 'non-' prefixed form rose with twentieth-century safety and environmental regulation, where a clear paired contrast with 'hazardous' was needed on labels and in legal text.