actinium series

noun, Chemistry
1.
the radioactive series that starts with uranium 235 and ends with a stable isotope of lead of mass number 207.
Origin
1955-60
Examples from the web for actinium series
  • These are the uranium series, the thorium series, and the actinium series.
  • The majority of these can be grouped into the uranium series, the actinium series, and the thorium series.
British Dictionary definitions for actinium series

actinium series

noun
1.
a radioactive decay series that starts with uranium-235 and ends with lead-207