californium

noun

cal·​i·​for·​ni·​um ˌka-lə-ˈfȯr-nē-əm 

: 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

It’s expected that more elements lay beyond the edge of the periodic table, but unfortunately californium is the heaviest element that can be used as a target – the next ones up are too unstable. —Michael Irving, New Atlas, 25 July 2024

This could be done by firing titanium at a californium target – although it’s expected to be an even rarer occurrence. —Michael Irving, New Atlas, 25 July 2024

So for instance, to make the element oganesson, which has 118 protons, scientists usually fire a beam of calcium (with 20 protons) at a target made of californium (with 98 protons). —Michael Irving, New Atlas, 25 July 2024

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, 12 Feb. 2021

Word History

Etymology

New Latin, from California, U.S.

First Known Use

1950, in the meaning defined above

Kids Definition

californium

noun

cal·​i·​for·​ni·​um ˌkal-ə-ˈfȯr-nē-əm 

: an artificially prepared radioactive element see element

Medical Definition

californium

noun

cal·​i·​for·​ni·​um ˌkal-ə-ˈfȯr-nē-əm 

: an artificially prepared radioactive element discovered by bombarding an isotope of curium with alpha particles

—symbol Cf see Chemical Elements Table