radioactive

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adjective ra·dio·ac·tive \ˌrā-dē-ō-ˈak-tiv\

Definition of radioactive

  1. :  of, caused by, or exhibiting radioactivity

radioactively

adverb

Examples of radioactive in a sentence

  1. Uranium and plutonium are radioactive.

Origin and Etymology of radioactive

International Scientific Vocabulary


First Known Use: 1898


RADIOACTIVE Defined for English Language Learners

radioactive

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adjective ra·dio·ac·tive \ˌrā-dē-ō-ˈak-tiv\

Definition of radioactive for English Language Learners

  • : having or producing a powerful and dangerous form of energy (called radiation)


RADIOACTIVE Defined for Kids

radioactive

play
adjective ra·dio·ac·tive \ˌrā-dē-ō-ˈak-tiv\

Definition of radioactive for Students

  1. :  caused by or exhibiting radioactivity <a radioactive element>


Medical Dictionary

radioactive

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adjective ra·dio·ac·tive \ˌrād-ē-ō-ˈak-tiv\

Medical Definition of radioactive

  1. :  of, caused by, or exhibiting radioactivity <radioactive isotopes>

radioactively

adverb


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