haf·​ni·​um ˈhaf-nē-əm How to pronounce hafnium (audio)
: a metallic element that occurs especially in zirconium minerals and is used in control rods for nuclear reactors see Chemical Elements Table

Example Sentences

Recent Examples on the Web And many metals have production losses of 95 percent or higher: arsenic, gallium, germanium, hafnium, scandium, selenium, and tellurium. John Timmer, Ars Technica, 20 May 2022 At this point, the whole device is covered with a thin layer of hafnium oxide, an insulator that provided a bit of space between the gate and the rest of the hardware. John Timmer, Ars Technica, 10 Mar. 2022 The firm's Rare Metals division produces, reclaims, refines, and markets high-value niche metals and compounds that include gallium, indium, rhenium, tantalum, niobium, and hafnium. Moneyshow, Forbes, 19 Mar. 2021 But today who needs to know the capital of South Dakota or the atomic number of hafnium (Pierre and 72)? Louis Menand, The New Yorker, 16 Nov. 2020 Per the paper, the analysis determined that ratios of hafnium isotopes can be used to differentiate Alexandrian glass from Levantine glass decolorized with manganese. Alex Fox, Smithsonian Magazine, 5 Aug. 2020 To avoid this issue, Barfod and her colleagues decided to look into the relative ratios of isotopes of the element hafnium. Alex Fox, Smithsonian Magazine, 5 Aug. 2020 One notable example was the discovery of three particularly rare elements found — hafnium, uranium and tungsten. Fox News, 1 Aug. 2019 This turned out to be a layer of hafnium oxynitride just eight atoms thick. Daniel Oberhaus, WIRED, 11 July 2019 See More

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

Word History


New Latin, from Hafnia (Copenhagen), Denmark

First Known Use

1923, in the meaning defined above

Time Traveler
The first known use of hafnium was in 1923

Dictionary Entries Near hafnium

Cite this Entry

“Hafnium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/hafnium. Accessed 4 Dec. 2022.

Kids Definition



haf·​ni·​um ˈhaf-nē-əm How to pronounce hafnium (audio)
: a gray metallic element that is useful because of its ready absorption of neutrons see element

Medical Definition



haf·​ni·​um ˈhaf-nē-əm How to pronounce hafnium (audio)
: a metallic element that resembles zirconium chemically, occurs in zirconium minerals, and readily absorbs neutrons
symbol Hf
see Chemical Elements Table

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