radioactive
/ˌreɪ.di.əʊˈæk.tɪv/ IELTSAcademic
adjective
Radioactive material gives out invisible energy called radiation. It can be dangerous and must be handled carefully.
- The lab stores radioactive waste safely.
- This rock is slightly radioactive.
- Workers wore protective gear near the radioactive source.
Adinary Nuance
Radioactive is more specific than dangerous or toxic. It points to radiation, not just general harm. Use it when the risk comes from atoms giving off energy, not from poison, heat, or germs.
In other languages
- Vietnamese
- phóng xạ
- Spanish
- radiactivo
- Chinese
- 放射性的
- Japanese
- 放射性の
- Korean
- 방사성의
Etymology
Radioactive combines radio-, from Latin radius, with active. It was first used in the late 1800s, after scientists discovered radiation from certain elements.
Common phrases
radioactive materialradioactive wasteradioactive decayradioactive contamination
Synonyms
Related words
Frequently asked questions
- Is radioactive the same as nuclear?
- No. Nuclear is broader. Radioactive means something gives off radiation.
- Is radioactive always dangerous?
- Often, yes. But some radioactive materials are weak and carefully controlled.
- Can I use radioactive in everyday writing?
- Yes, but mostly for science, health, or safety topics.