radioactivity

/ˈreɪdioʊækˌtɪvədi/

Other forms: radioactivities

The emission of energy in a stream of particles or waves is radioactivity. While radioactivity can be useful in science and medicine, exposure to high doses of it is dangerous.

Archaeologists can learn the age of certain fossils by measuring their radioactivity — or more specifically, the amount of radioactive carbon they contain. Radioactivity is what creates nuclear power, and doctors also use it in radiation therapy, to kill cancer cells. Too much radioactivity is bad for our bodies, though, since it can damage our DNA. The word comes from radioactivité, which was coined by Marie and Pierre Curie in 1898.

Definitions of radioactivity

1. noun

   the spontaneous emission of a stream of particles or electromagnetic rays in nuclear decay
   synonyms: radiation

   types:

   corpuscular radiation, particulate radiation

   a stream of atomic or subatomic particles that may be charged positively (e.g. alpha particles) or negatively (e.g. beta particles) or not at all (e.g. neutrons)

   alpha radiation, alpha ray

   the radiation of alpha particles during radioactive decay

   beta radiation, beta ray, electron radiation

   radiation of beta particles during radioactive decay

   neutron radiation

   radiation of neutrons (as by a neutron bomb)

   type of:

   emission

   the release of electrons from parent atoms