Definition of radioactive
: of, caused by, or exhibiting radioactivity
Examples of radioactive in a sentence
Uranium and plutonium are radioactive.
Origin and Etymology of radioactive
International Scientific Vocabulary
First Known Use: 1898
RADIOACTIVE Defined for English Language Learners
Definition of radioactive for English Language Learners
: having or producing a powerful and dangerous form of energy (called radiation)
RADIOACTIVE Defined for Kids
Definition of radioactive for Students
: caused by or exhibiting radioactivity a radioactive element
Seen and Heard
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