reverse search

Comprehensive
Dictionary Suite
Help
Help
Help
 
pitchblende a naturally occurring dark-colored mineral that is a major source of uranium and radium.
Ra1 symbol of the chemical element radium.
radium therapy the treatment of disease, esp. cancer, by means of radium.
radon a radioactive chemical element of the inert gas group that has eighty-six protons in each nucleus and that is produced by the radioactive decay of trace amounts of radium in the soil. (symbol: Rn)