hafnium

American  

[haf-nee-uhm, hahf-] / ˈhæf ni əm, ˈhɑf- /

noun

Chemistry.

1. a gray, toxic metallic element with a high melting point (over 2000°C), found in most zirconium minerals. Hf; 178.49; 72; 12.1.

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hafnium British  

/ ˈhæfnɪəm /

noun

1. a bright metallic element found in zirconium ores: used in tungsten filaments and as a neutron absorber in nuclear reactors. Symbol: Hf; atomic no: 72; atomic wt: 178.49; valency: 4; relative density: 13.31; melting pt: 2231±20°C; boiling pt: 4603°C

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hafnium Scientific  

/ hăf′nē-əm /

1. A bright, silvery metallic element that occurs in zirconium ores. Because hafnium absorbs neutrons better than any other metal and is resistant to corrosion, it is used to control nuclear reactions. Atomic number 72; atomic weight 178.49; melting point 2,220°C; boiling point 5,400°C; specific gravity 13.3; valence 4.

2. See Periodic Table

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Etymology

Origin of hafnium

1923; < New Latin Hafn ( ia ) Copenhagen + -ium

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Example Sentences

See Examples For:

hafnium

Because hafnium oxide is already compatible with existing semiconductor manufacturing, integrating this new memory into everyday electronics could happen relatively quickly.

From Science Daily ● May 3, 2026

One notable example was the discovery of three particularly rare elements found — hafnium, uranium and tungsten.

From Fox News ● Aug. 1, 2019

Control rods are made of boron, cadmium, hafnium, or other elements that are able to absorb neutrons.

From Textbooks ● Feb. 14, 2019

That means that future scientists won’t be able to date the Martian rocks using a radioactive decay system that relies on tungsten and hafnium; they will have to choose from several other alternatives.

From Nature ● Jan. 17, 2017

"If you stay within a half mile of the hafnium pile, the detection man will not be able to pick up your radiation and maybe you will have a second chance."

From The Stutterer by R. R. Merliss

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