hafnium

noun

haf·​ni·​um ˈhaf-nē-əm 

: a metallic element that occurs especially in zirconium minerals and is used in control rods for nuclear reactors see Chemical Elements Table

Examples of hafnium in a Sentence

Recent Examples on the Web

Our experiment uses hafnium monofluoride molecules because hafnium, with 72 protons in its nucleus, is one of the heaviest metals in the periodic table that isn't radioactive. —Luke Caldwell, Scientific American, 1 Feb. 2024

It’s constructed from alternating thin films of hafnium oxide (HfO2) and glass sitting on top of a silver reflective layer. —Sid Assawaworrarit, IEEE Spectrum, 25 Nov. 2023

Any hafnium stays happily in the mantle and keeps on decaying into tungsten, which then remains in the silicate mantle if no further core formation occurs. —Linda T. Elkins-Tanton, Scientific American, 1 Dec. 2016

This decay happens on a regular schedule: half the hafnium turns into tungsten in nine million years. —Linda T. Elkins-Tanton, Scientific American, 1 Dec. 2016

Word History

Etymology

New Latin, from Hafnia (Copenhagen), Denmark

First Known Use

1923, in the meaning defined above

Kids Definition

hafnium

noun

haf·​ni·​um ˈhaf-nē-əm 

: a gray metallic element that is useful because of its ready absorption of neutrons see element

Medical Definition

hafnium

noun

haf·​ni·​um ˈhaf-nē-əm 

: a metallic element that resembles zirconium chemically, occurs in zirconium minerals, and readily absorbs neutrons

—symbol Hf see Chemical Elements Table