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

Example Sentences

Their research helped advance the use of hafnium oxide, which later became the standard material used in computer processors and mobile devices beginning in the mid-aughts.

From Science Daily • Mar. 5, 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

Such demands necessitate the use of alloys of exotic metals such as rhenium, hafnium, nickel and titanium to provide the performance, efficiency and weight savings required for today's advanced aircraft engines.

From Nature • Mar. 22, 2016

In its very center, buried in a mine of graphite were the tubes of hafnium, from whose nuclear explosions flowed a river of electricity without the need of human thought or direction.

From The Stutterer by Merliss, R. R.