cal·​i·​for·​ni·​um | \ ˌka-lə-ˈfȯr-nē-əm How to pronounce californium (audio) \

Definition of californium

: a radioactive chemical element with atomic number 98 that is produced artificially from the decay of berkelium and that is used chiefly as a neutron source in radiography and to start nuclear reactors — see Chemical Elements Table

Examples of californium in a Sentence

Recent Examples on the Web But the chase for 120 is on hold until researchers obtain the amount of californium—a rare element produced in high-flux nuclear reactors—needed for 120’s target. Daniel Clery, Science | AAAS, "Hopes evaporate for the superheavy element flerovium having a long life," 12 Feb. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'californium.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of californium

1950, in the meaning defined above

History and Etymology for californium

New Latin, from California, U.S.

Keep scrolling for more

Learn More about californium

Time Traveler for californium

Time Traveler

The first known use of californium was in 1950

See more words from the same year

Statistics for californium

Cite this Entry

“Californium.” Dictionary, Merriam-Webster, Accessed 6 May. 2021.

Style: MLA
MLACheck Mark Icon ChicagoCheck Mark Icon APACheck Mark Icon Merriam-WebsterCheck Mark Icon

Keep scrolling for more

More Definitions for californium


cal·​i·​for·​ni·​um | \ ˌkal-ə-ˈfȯr-nē-əm How to pronounce californium (audio) \

Medical Definition of californium

: an artificially prepared radioactive element discovered by bombarding an isotope of curium with alpha particles symbol Cf — see Chemical Elements Table

More from Merriam-Webster on californium Encyclopedia article about californium

Comments on californium

What made you want to look up californium? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

Star Wars Words Quiz

  • cu jedi training
  • The bounty portion of bounty hunters (such as Boba Fett) comes from a Latin word meaning
Name That Thing

Test your visual vocabulary with our 10-question challenge!


Anagram puzzles meet word search.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!