Simple Definition of radioactive
: having or producing a powerful and dangerous form of energy (called radiation)
Full Definition of radioactive
: of, caused by, or exhibiting radioactivity
Examples of radioactive
Uranium and plutonium are radioactive.
Origin of radioactive
International Scientific Vocabulary
First Known Use: 1898
RADIOACTIVE Defined for Kids
Definition of radioactive
: caused by or exhibiting radioactivity <a radioactive element>
Medical Definition of radioactive
: of, caused by, or exhibiting radioactivity <radioactive isotopes>
Seen and Heard
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