radon

play
noun ra·don \ˈrā-ˌdän\

Definition of radon

  1. :  a heavy radioactive gaseous element formed by the decay of radium — see element table

Origin and Etymology of radon

International Scientific Vocabulary, from radium


First Known Use: 1918


RADON Defined for English Language Learners

radon

play
noun ra·don \ˈrā-ˌdän\

Definition of radon for English Language Learners

  • : a radioactive element which is a gas that is used medically in cancer treatments


Medical Dictionary

radon

play
noun ra·don \ˈrā-dän\

Medical Definition of radon

  1. :  a heavy radioactive gaseous element of the group of inert gases formed by disintegration of radium and used similarly to radium in medicine—symbol Rn; called also radium emanation; see element table



Seen and Heard

What made you want to look up radon? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

to criticize severely

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ