Dictionary.com
Thesaurus.com

neptunium series

British  

noun

  1. a radioactive series that starts with plutonium-241 and ends with bismuth-209. Neptunium-237 is the longest-lived member of the series. The series does not occur in nature

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The neptunium series, previously thought to terminate with bismuth-209, terminates with thallium-205.

From Textbooks • Feb. 14, 2019

The neptunium series is a fourth series, which is no longer significant on the earth because of the short half-lives of the species involved.

From Textbooks • Feb. 14, 2019