radium
/ˈɹeɪ.di.əm/ noun B2- The chemical element (symbol Ra) with an atomic number of 88. It is a soft, shiny and silvery radioactive alkaline earth metal.
- An atom of this element.
- A type of cloth woven from silk or synthetic yarn, often with a shiny appearance.
Plural radiums
Learn radium in real texts
With a free account, hover any word in the library for its meaning, hear it read aloud, save words for review timed to your memory, and see how much of each book you already know.